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Tibialis Posterior Tendon Dislocation: A Review and Suggested Classification
The Journal of Foot & Ankle Surgery xxx (2017) 1–10
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Case Reports and Series
Tibialis Posterior Tendon Dislocation: A Review and Suggested Classification Andrew Strydom, MBBCh(Wits), FCOrth(SA), MMed(OrthoSurg) (Wits) 1, 2, Nikiforos Pandelis Saragas, MBBCh(Wits), FCS (SA) Ortho, MMed(OrthoSurg) (Wits) 3, 4, Makgabo Tladi, MBChB(Limpopo), FCOrth(SA) 1, 5, Paulo Norberto Farria Ferrao, MBChB(Pret), FCS (SA) Ortho 2, 6 1
Fellow, The Orthopaedic Foot and Ankle Unit, Netcare Linksfield Hospital, Johannesburg, South Africa Consultant Orthopaedic Surgeon, Department of Orthopaedic Surgery, University of the Witwatersrand, Johannesburg, South Africa 3 Director, The Orthopaedic Foot and Ankle Unit, Netcare Linksfield Hospital, Johannesburg, South Africa 4 Honorary Adjunct Professor, Department of Orthopaedic Surgery, University of the Witwatersrand, Johannesburg, South Africa 5 Consultant Orthopaedic Surgeon, Dr George Mukhari Academic Hospital, Sefako Makgatho Health Science University, Ga-Rankuwa, South Africa 6 Assistant Director, The Orthopaedic Foot and Ankle Unit, Netcare Linksfield Hospital, Johannesburg, South Africa 2
a r t i c l e i n f o
a b s t r a c t
Level of Clinical Evidence: 4
Tibialis posterior tendon dislocation is a rarely described entity that is easily missed, resulting in delayed diagnosis and treatment. A review of the English published data on the topic showed inconsistency in the reporting of injuries and surgical management techniques, leading us to describe a novel classification system to guide treatment and future reporting. We also describe a case of tibialis posterior tendon dislocation in a professional volleyball player and our surgical technique for correction, including retromalleolar groove deepening. Ó 2017 by the American College of Foot and Ankle Surgeons. All rights reserved.
Keywords: classification flexor retinaculum groove deepening retromalleolar groove tendon dislocation tibialis posterior tendon
Tibialis posterior tendon dislocation (TPD) is a relatively rare entity, and the English published data on the topic is limited to case reports and small series (1–26). Since the first description of a traumatic case in 1968 (3), a small, but consistently growing, collection of cases, mostly with a traumatic etiology (1,2,4,7,11,15–18,20,24,26), has emerged. Unlike peroneal tendon injuries, for which the mechanism of injury, association with ankle injuries, diagnostic modalities, and management through surgical stabilization have been well described (27,28), the natural history and treatment guidelines of TPD are unclear. The present study reviewed the available English data, which informs the description of our case management for a professional volleyball player. Systematic Review of the Published Data A summary of the data published in English (including our case) are listed in Tables 1 and 2. A total of 38 cases have been reported from 1968 to 2016, including 20 males (53%) and 18 females (47%). Of the Financial Disclosure: None reported. Conflict of Interest: None reported. Address correspondence to: Andrew Strydom, MBBCh(Wits), FCOrth(SA), MMed(OrthoSurg) (Wits), Orthopaedic Foot and Ankle Unit, Netcare Linksfield Hospital, 24 12th Avenue, Suite 303, Linskfield West, Johannesburg 2193, South Africa. E-mail address: [email protected] (A. Strydom).
38 cases, 27 (71%) occurred before the patient was 40 years old. For 8 cases (21%), the affected side was not reported, 16 cases (53%) were right-sided, and 14 were left-sided (37%). The predominant mechanism of injury involved a foot fixed to the floor with a twisting injury, consisting of forced eversion and dorsiflexion in 28 cases (68%). For the remaining 10 cases, the cause of injury was a high-energy motor vehicle accident in 3, an unclear mechanism in 3, iatrogenic in 2, spontaneous recurrence in 1, and Chopart’s joint dislocation in 1. The prevailing symptom associated with TPD is medial ankle pain, which was present in 29 cases (76%). Persistent swelling was present in 17 cases (45%), and an associated sensation of instability/clicking/ snapping was present in 17 cases (45%) and are other common symptoms. Medial ankle pain combined with persistent swelling and/ or a sensation of instability/clicking/snapping occurred in 24 cases (63%). An inability to weight bear in 3 patients and locking in 1 patient were the only other described symptoms. The posterior tibialis tendon (PTT) was dislocated or dislocatable on physical examination in 23 patients (60%). The interval from injury to surgery was reported for 37 patients (97%); the calculated mean interval to surgery was 17.3 weeks (range 0 to 96). The most common retinacular pathologic feature noted at surgery was anterior avulsion of the flexor retinaculum off the medial
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Table 1 Summary of patient characteristics from a systematic review of data published in English Investigator
Patients (n)
Gender
Age (yr)
Side
Injury Mechanism
Symptoms/Findings
Interval to Surgery (wk)
Swelling
Subluxing Sensation, Snapping, Clicking
Other
PTT Subluxed or Dislocatable at Examination
Yes Yes Yes
NR NR NR
Yes Yes Yes
NR NR NR
Yes Yes No
NR 28 8
Yes Yes
NR NR
NR NR
NR Locking
Yes No
2 5
Yes
NR
Yes
NR
Yes
96
Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes NR Yes
NR NR Yes NR Yes NR Yes Yes Yes NR NR NR
Yes Yes NR NR NR NR Yes Yes NR NR Yes Yes
NR NR NR NR NR NR NR NR NR NR NR NR
Yes Yes Yes No Yes No No Yes No Yes Yes No
0 0 9 1 0 72 4 16 96 2 12 48
Yes
NR
NR
Yes
20
Yes
0
No No No No Yes
2 0 32 24 20
Nava et al (3), 1968 Sharon et al (23), 1978 Langan et al (10), 1980
1 1 1
Male Male Female
16 37 16
Left Right NR
Larsen et al (11), 1984 Recurrent case
2
Male Female
18 36
Left Left
Stanish et al (25), 1984
1
Female
16
Right
Soler et al (24), 1986 Mittal et al (16), 1988 Perlman et al (20), 1990
1 1 2
Biedert (5), 1992 Ouzounian et al (19), 1992
1 7
Male Male Male Male Male Female Female Male Female Male Male Female
39 40 36 27 18 44 17 24 55 42 38 26
Right Left Right Left Right NR NR NR NR NR NR NR
Healy et al (9), 1995
1
Male
14
Right
MVA MVA Iatrogenic, tarsal tunnel release Twist, running Spontaneous recurrence of previously surgically treated dislocation Spontaneous, unclear mechanism Twist, walking Twist, low energy Twist Twist Twist, gymnastics Twist Twist Twist Cortisone injections Twist PER Dislocation of Chopart’s joint Twist, low energy
Hatori et al (8), 1997
1
Female
48
Right
Twist, low-energy squat
Yes
NR
NR
Rolf et al (21), 1997
2
Gambhir et al (6), 1998 Loncarich et al (13), 1998 Miki et al (14), 1998
1 1 2
Male Female Male Male Female
37 53 37 37 41
Left Right Right Left Right
Yes Yes Yes Yes Yes
NR Yes Yes Yes NR
NR Yes NR NR Yes
Nuccion et al (17), 2001 Wong (26), 2004 Goucher et al (7), 2006
1 1 2
Female Male Male Female
41 31 24 27
Right Left Left Left
NR Yes NR Yes
NR Yes NR NR
Yes NR Yes NR
NR NR NR NR
Yes No Yes Yes
4 1 4 28
Sharma et al (22), 2006 Olive Vilas et al (18), 2009 Lohrer et al (12), 2010 Mitchell et al (15), 2011
1 1 1 1
Male Female Female Male Female
37 14 17 57 56
NR Left Right Right Right
Twist, ice skating Twist Twist, cricket (bowling) Twist, rock climbing Twist, low energy, rising from seated Twist, low-energy squat Unclear, sprinting, soccer Playing basketball Twist, running (treated with cortisone injection) Twist, water-skiing Twist, running Twist, Tae-kwon-do Twist, rock climbing Twist, low-energy squat
Unable to bear weight Unable to bear weight NR NR NR NR NR
Yes Yes Yes Yes Yes
NR Yes Yes Yes Yes
NR Yes Yes NR NR
Yes Yes Yes No Yes
1 32 8 28 3
Al Khudairy et al (4), 2013 Gambardella et al (1), 2014 Mullens et al (2), 2015 Present case, 2016
1 1 1 1
Female Male Female Female
17 19 19 41
Left Left Right Right
MVA Unclear, snow boarding Twist, gymnastics Twist, volleyball
Yes Yes Yes Yes
Yes Yes Yes Yes
NR NR NR Yes
NR NR NR NR Unable to bear weight NR NR NR NR
No Yes No Yes
0 28 1 4
Abbreviations: MVA, motor vehicle accident; NR, not reported.
A. Strydom et al. / The Journal of Foot & Ankle Surgery xxx (2017) 1–10
Medial Ankle Pain
Table 2 Summary of pathologic findings from systematic review of data published in English Investigator
Pathologic Findings Groove
Nava et al (3), 1968 Sharon et al (23), 1978
Torn
Langan et al (10), 1980 Larsen et al (11), 1984 Recurrent case Stanish et al (25), 1984 Soler et al (24), 1986 Mittal et al (16), 1988 Perlman et al (20), 1990
Biedert (5), 1992 Ouzounian et al (19), 1992
Healy et al (9), 1995 Hatori et al (8), 1997
Treatment Other
Primary Repair Retinaculum Reconstruction
Immobilization
Normal NR
No
No
Yes
No
10-wk Cast immobilization NR
NR
Shallow NR
No
No
No
5-wk Cast immobilization
Progressive WB from day 5 postoperatively
21
Full recovery
Deficient
Shallow NR
Yes, medial malleolus bone block Yes
No
No
Yes, periosteal flap
Full recovery
NR
NR
No
No
Yes
No
Unlimited walking 4 wk postoperatively NR
36
Torn
4-wk Cast immobilization, WB 6-wk Cast immobilization
12
Full recovery
Avulsion Deficient
NR NR
NR NR
No Yes
Yes, sutures No
No No
No 5-wk Cast immobilization Yes, tenosynovial flap Compressive bandage
36 48
Full recovery Full recovery
Avulsion
Shallow NR
No
Yes, sutures
No
Yes, periosteal flap
3-wk Cast immobilization
NR Progressive WB from day 2 postoperatively 2-wk Physiotherapy
24
Full recovery
Avulsion
NR
No
Yes, sutures
No
No
6
Full recovery
Avulsion, fleck Shallow NR
Yes, bone wedge
Yes, sutures
No
No
3-wk Cast immobilization, plantarflexion 4-wk Cast immobilization
11
Full recovery
Avulsion
Shallow NR
Yes, bone wedge
Yes, sutures
No
No
8-wk Cast immobilization
18
Full recovery
Torn
Normal NR
No
No
Yes, sutures
No
4-wk Night splinting
2,5
Full recovery
Deficient
No Shallow Tendon inflamed with tears
Yes, sutures, No FDL tenodesis
No
4- to 6-wk Cast immobilization
Absent
Normal Tendon inflamed
No
No
No
Yes, deltoid and FDL sheath
4- to 6-wk Cast immobilization
Absent
Shallow NR
No
Yes
No
Yes
4- to 6-wk Cast immobilization
Absent
Normal Inflamed
No
No
No
Yes, periosteum and FDL sheath
4- to 6-wk Cast immobilization
Avulsion Normal NR (bony fleck)
No
Yes, sutures
No
No
4- to 6-wk Cast immobilization
Avulsion Shallow NR (bony fleck)
No
Yes, sutures
No
No
4- to 6-wk Cast immobilization
Deficient
Shallow NR
Yes
Yes, sutures
No
No
4- to 6-wk Cast immobilization
Deficient
Shallow NR
Yes
No
No
Yes, periosteal flap
3-wk Cast immobilization
Avulsion
Normal NR
No
Yes, sutures
No
No
5-wk Cast immobilization
NR
Rehabilitation
Follow-Up Reported (mo) Outcome
Groove Deepening Retinacular Reattachment
NR ROM and progressive WB over 2 wk Progressive WB from 4 wk, then proprioception and strength training NWB 6 wk, then functional rehabilitation Mobilization, strengthening, proprioception until recovery Mobilization, strengthening, proprioception until recovery Mobilization, strengthening, proprioception until recovery Mobilization, strengthening, proprioception until recovery Mobilization, strengthening, proprioception until recovery Mobilization, strengthening, proprioception until recovery Mobilization, strengthening, proprioception until recovery WB from day 1, then 3 wk air brace NR
NR
1
Full recovery
Improved
44
Full recovery
38
Full recovery
32
Occasional symptoms
14
Full recovery
14
Full recovery
16
Full recovery
2
Full recovery
24
Full recovery
3
(continued on next page)
A. Strydom et al. / The Journal of Foot & Ankle Surgery xxx (2017) 1–10
Retinaculum
Investigator
4
Table 2 (continued ) Pathologic Findings
Immobilization
Rehabilitation
Normal NR
No
No
No
Yes, TA strip
6-wk Cast immobilization
Avulsion
Normal NR
No
Yes
No
No
6-wk Cast immobilization
Gambhir et al (6), 1998
Avulsion
Normal Bony spur
No
No
No
None
Loncarich et al (13), 1998 Miki et al (14), 1998
Avulsion
Normal Synovitis
No, tendon decompression and spur excision No
Strength, flexibility, proprioceptive training Strength, flexibility, proprioceptive training Physiotherapy
Yes, sutures
No
No
Deficient
Shallow NR
No
No
No
Physiotherapy, CAM boot for 7 wk NR
Avulsion
Shallow NR
No
No
No
6-wk Cast immobilization
NR
Avulsion
Normal NR
Yes, shelf or bone block Yes, shelf or bone block No
4-wk Cast immobilization, NWB 5-wk Cast immobilization
No
No
6-wk Cast immobilization
Avulsion
NR
No
No
No
Avulsion
Shallow Tears in tendon
Yes
Yes, suture anchors Yes, suture anchors Yes, sutures
No
No
Avulsion Avulsion
NR NR Normal NR
Yes No
Yes, sutures Yes, sutures
No No
No No
Avulsion
Normal NR
No
Yes, sutures
No
No
Avulsion
No
Yes
No
No
Avulsion
Normal Tears in tendon Normal NR
No
Yes, sutures
No
No
Avulsion
NR
No
Yes, sutures and anchor
No
Yes
Yes, sutures
No
Yes
Goucher et al (7), 2006
Sharma et al (22), 2006 Olive Vilas et al (18), 2009 Lohrer et al (12), 2010 Mitchell et al (15), 2011 Al Khudairy et al (4), 2013 Gambardella et al (1), 2014 Mullens et al (2), 2015
Deficient
Avulsion Avulsion
Present case, 2016 Avulsion
Other
NR
Medial malleolus fracture Shallow Tears in tendon Normal Tears in tendon, tibial OCD Shallow Tears in tendon
Physiotherapy, WB as tolerated in CAM boot 4-wk Cast immobilization, Physiotherapy for ROM and inversion, equinus, NWB strengthening Physiotherapy, crossCAM boot, WB at 1 wk training plus ROM, FWB at 6 wk with removable brace NR NR 6-wk Cast immobilization, Physiotherapy, ROM, NWB strengthening, proprioception 5-wk BK cast Functional rehabilitation
Follow-Up Reported (mo) Outcome
12
Full recovery
12
Full recovery
NR
Full recovery
8
Full recovery
144
Full recovery
24
Full recovery
5
Full recovery
11
Full recovery
13
Full recovery
6 12
Full recovery Full recovery
3
Full recovery
6
Full recovery
18
Full recovery
1-wk BK cast, removable splint 6 wk 6-wk cast immobilization
Proprioceptive and strength training NR
No
6-wk NWB cast, PRWB to 12 wk
Progressive WB, active ROM
12
Full recovery
No
No
Physiotherapy, active ROM
12
Full recovery
Yes, buttress plate
No
No
4-wk NWB splint, 2-wk boot, physiotherapy 6-wk NWB cast, boot with PRWB
Physiotherapy, active ROM
12
Full recovery
Yes, sutures
No
No
3
Full recovery
4-wk NWB cast, PRWB in boot
Physiotherapy, ROM, proprioception
Abbreviations: BK, below the knee; CAM, controlled ankle motion; FDL, flexor digitorum longus; NWB, non-weightbearing; NR, not reported; OCD, osteochondritis dissecans; PRWB, partial weightbearing; ROM, range of motion; WB, weightbearing.
A. Strydom et al. / The Journal of Foot & Ankle Surgery xxx (2017) 1–10
Primary Repair Retinaculum Reconstruction
Nuccion et al (17), 2001 Wong (26), 2004
Groove
Treatment Groove Deepening Retinacular Reattachment
Rolf et al (21), 1997
Retinaculum
A. Strydom et al. / The Journal of Foot & Ankle Surgery xxx (2017) 1–10
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additional report described retinaculum reattachment with a buttress plate in 1 patient. A groove deepening procedure was performed in 13 cases (34%). In 2 patients with a shallow groove, the groove was not deepened, and in 2 cases with no description of the groove depth, the groove depth was deepened. All 3 cases (8%) with a torn retinaculum were managed by primary suturing of the retinaculum. In 10 cases (26%), a deficient retinaculum was reported, with 8 undergoing retinacular reconstruction. In 4 of the reconstruction procedures, a periosteal flap was used. Two cases included a groove deepening procedure. Postoperative cast immobilization was used in 34 cases (89%), with a mean duration of immobilization of 5 weeks (range 1 to 10). In 1 case, the patient was not immobilized at all, 1 patient used a removable night splint, 1 used a compression bandage, and for 1 case, immobilization was not specified. In 27 cases (70%), the patient underwent rehabilitation with physiotherapy exercises of variable quality and purpose. A rehabilitative protocol was not described or the information was unavailable for 11 patients. The functional outcome was reported as full recovery in 36 cases (95%), with a mean final follow-up duration of 19.8 months (range 3 to 144). Also, for 2 patients from the same series improved outcomes with occasional symptoms were reported. Fig. 1. Anteroposterior radiographs showing “fleck sign” (yellow arrow).
Case Report malleolus in 24 cases (63%), followed by a deficient or an absent retinaculum in 10 (26%) and a tear in the substance of the retinaculum in 3 (8%). The status of the retinaculum was not reported for 1 case. The retromalleolar groove was described as shallow in 15 cases (39%). No description was provided regarding the depth of the groove in 6 cases (16%). The associated pathologic features noted at surgery included 6 PTT tears (16%), 4 cases with concomitant inflammation or synovitis (11%), 1 bony spur on the medial malleolus, 1 medial malleolus fracture, and 1 tibial plafond osteochondral defect. The most common surgical procedure performed was retinacular reattachment to the medial malleolus (as described for peroneal tendon subluxation) in 23 cases (61%). In 1 of these cases, a deficient retinaculum was repaired and augmented with a flexor digitorum longus (FDL) tenodesis. In 3 of the cases, suture anchors were used instead of, or in conjunction with, transosseous tunnels. One
We present the case of a 41-year-old healthy professional volleyball player with a history of repeated right ankle injuries and associated instability, in particular, during competitive games. Two weeks before the referral from her physiotherapist, she heard and/or felt a pop over her medial ankle during a volleyball game. The ankle swelled immediately, and she was unable to bear weight on it. This was the most painful injury in her recent memory. She experienced the same symptoms again during evaluation by the physiotherapist with the ankle placed in a position of resisted inversion. She was immobilized in a pneumatic immobilizer boot and referred for further assessment. She was a nonsmoker with no medical comorbidities or allergies. The physical examination revealed a swollen right ankle with a right-sided antalgic gait. She was unable to walk on her toes or heels because of the pain. The right calf and Achilles tendon were soft and not tender. The PTT was tender and boggy on palpation, consistent
Fig. 2. Ultrasound image confirming tibialis posterior dislocation and avulsion of flexor retinaculum with fleck of bone visible.
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Fig. 3. Positioning and surface anatomy.
Fig. 5. Shallow retromalleolar groove.
with associated synovitis. The medial gutter of the ankle, medial malleolus, and deltoid ligaments were moderately tender. The anterior joint line of the ankle was mildly tender. The ankle range of motion was limited owing to pain. Her hindfoot range of motion was normal. Resisted inversion of the foot resulted in obvious and painful dislocation of the PTT over the medial malleolus. The rest of the examination findings were unremarkable, with no neurovascular deficit present. Standard weightbearing radiographs of the ankle were obtained, and careful examination revealed a “fleck sign” on the anteroposterior radiograph at the level of the medial malleolus (Fig. 1). The patient had been previously referred for ultrasound evaluation of the right ankle and foot, which revealed a poorly visualized anterior talofibular ligament and 2 small bony fragments in the deltoid ligament, both consistent with previous injuries. A small ankle effusion was noted. However, the ultrasound report had no comment on the PTT position or quality, necessitating a second ultrasound examination. The second ultrasound examination confirmed the findings of the previous investigation, with the addition of a small (6.2 1.1 4.8 mm) bony fragment, consistent with avulsion of the superior insertion of the medial flexor retinaculum off the medial malleolus (Fig. 2). Dynamic assessment of the PTT confirmed anterior subluxation over the medial malleolus deep to the aforementioned bony fragment. The PTT showed evidence of synovitis and a hypoechoic section of the medial most-fibers at the level of the subluxation,
possibly from early tendinopathy. The flexor hallucis longus, flexor digitorum longus, and peroneal tendons were uninjured. After a discussion of the ultrasound results and treatment options, the patient elected for surgical reconstruction.
Fig. 4. Avulsion of the flexor retinaculum with the subluxed tibialis posterior tendon.
Surgical Procedure The patient was prepared and draped under general anesthesia with a popliteal nerve block, tourniquet, and a bolster under the contralateral hip to facilitate access with the leg in external rotation. The surface anatomy of the medial malleolus, navicular tuberosity, and course of the PTT were drawn using a Codman marker (Fig. 3). The skin incision was continued down to the flexor retinaculum. The retinaculum was then incised over the posterior border of the medial malleolus and was noted to have avulsed from the malleolus with a small bony sleeve (Fig. 4). The tendon itself was synovitic, with multiple small tears. The retromalleolar groove for the PTT was shallow (Fig. 5). We decided to perform a groove deepening procedure. Sequential linear drill holes (1.5-mm drill) were made along the posteromedial and posterolateral border of the medial malleolus for approximately 3 cm. The 2 borders were then connected proximally with drill holes. The drill holes were then connected using a small oscillating saw or sharp osteotome. The bone flap was elevated, with a hinge distally on the tip of the medial malleolus. The underlying cancellous bone was removed using a spine curette to form a void. The outer cortex was returned to its place and carefully impacted into the void. A squareshaped bone punch should preferably be used. This technique maintains the fibrocartilaginous surface of the groove and minimizing adhesion formation (Fig. 6). The tendon was reduced and found to be stable within the deepened groove. All synovitis was debrided. The tendon itself was debrided and repaired with a braided absorbable suture. The medial surface of the medial malleolus is roughened using a rongeur or osteotome to allow the repaired retinaculum to scar down. The PTT was then reduced in its groove and the retinaculum repaired through 3 small drill holes in the posteromedial edge of the malleolus using a braided absorbable suture as demonstrated in Figs. 7 and 8. The tendon was observed to move freely within the retinaculum. The repair site was injected with platelet-rich plasma and the wound was closed in layers. Rehabilitation The foot was immobilized in a below-the-knee non-weightbearing cast for 4 weeks, after which the cast was removed. A pneumatic
A. Strydom et al. / The Journal of Foot & Ankle Surgery xxx (2017) 1–10
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Fig. 6. Groove deepening procedure.
immobilizer boot was fitted for a 2-week period, with progressive weightbearing as tolerated. Physiotherapy was initiated, which consisted of soft tissue mobilization, range of motion, and strengthening and proprioceptive exercises. At 8 weeks, the patient was evaluated again, and the PTT was in a reduced position without any evidence of subluxation during active or resisted movement. The patient only experienced mild discomfort on occasion and had progressed to strengthening exercises under the supervision of the physiotherapist. At 12 weeks postoperatively, the patient was well, with the PTT functioning at normal strength without evidence of subluxation. No evidence of synovitis or tendon injury remained at this point. At 18 months postoperatively, the patient had returned to competing at a national level. Discussion TPD was reported as uncommon in nearly every case report (1–26,29,30); however, our examination of the published data led us to believe that this entity might be more common than previously
thought. Two thirds of the cases reported a twisting force constituting a forced or resisted dorsiflexion-eversion injury (2,5–9,11–22,24), one half of which were sustained during a sporting activity. The published data support the likelihood of this injury occurring in younger patients (31), in particular, those aged <40 years engaging in sporting activity. Ankle injuries are possibly the most common musculoskeletal injuries, particularly in athletes; however, it is most commonly the lateral ligaments that are injured (32,33). Many of the case reports described a significant delay in diagnosis and, ultimately, in treatment (6,7,9,19,22), with an average time to surgery from injury of 17.3 weeks. Thus, we believe the true incidence of TPD might be greater than reported because it can often be overlooked or missed owing to a lack of awareness. With the described symptoms, any patient with persistent medial-sided ankle pain, with or without associated symptoms, should be carefully assessed for a missed TPD. A clearly dislocated or able to be dislocated PTT was evident in 60% of cases; thus, a careful history and examination should allow for a significant increase in diagnostic yield.
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Fig. 7. Tendon repair, reduction and retinacular repair.
For cases in which the diagnosis is still not clear, special investigations are warranted. Plain radiographs allow for the exclusion of most fractures and might reveal a bony avulsion at the level of the medial malleolus, which should raise suspicion for TPD, although this was only reported in 3 cases (19,20). Magnetic resonance imaging allows for study of the PTT position, retinacular injury, and depth of the retromalleolar groove. In 1 report, 100% of cases showed a clear PTT dislocation/subluxation with magnetic resonance imaging (31). Ultrasonography is operator dependent and less reproducible than magnetic resonance imaging but allows for low-cost, effective assessment and dynamic evaluation of the PTT position with an experienced operator (34). The PTT lies within a cartilage-lined retromalleolar groove on the tibia and is stabilized within it by the medial flexor retinaculum (35). This is virtually identical to the anatomic structure of the peroneal tendon groove on the fibula. It is thus reasonable to assume that similar pathologic processes can occur within these structures to produce a TPD. The pathology and classification of peroneal tendon dislocation by Eckert and Davis (29) is well accepted and follows a continuum of injury extent, with grade 1 injuries occurring more commonly than grade 3. The major pathology in TPD is insufficiency of the flexor retinaculum to contain the tendon, either in the form of torn or redundant tissue or avulsion of the anterior retinaculum off the medial malleolus. Similar to the peroneal side pathology, a bony avulsion of the retinaculum off the medial malleolus is less common, and was
reported in 4 cases (19,20). It is possible that this type of injury might be more common than reported; thus, radiographs must be carefully assessed for a “fleck sign,” because this subgroup might be amenable to nonoperative management. A shallow retromalleolar groove might increase the risk of peroneal tendon dislocation (28), and the same might be true for TPD. A groove deepening procedure, either in the form of burring away bone or functionally deepening the groove with a bony block/shelf-type procedure, was described in 7 cases, in conjunction with a retinacular procedure. Of the 3 patients without a groove deepening procedure, 2 were reported to have a full functional recovery (19,24) and 1 had residual symptoms (19). In contrast, all the patients who had undergone a groove deepening were reported to have full recovery. Using the available data, we suggest the following classification and treatment algorithm based on the type of retinacular pathology and depth of the retromalleolar groove (Table 3): Type 1: Avulsion injury (most common), with subtypes A and B, similar to the description by Eckert and Davis (29) for peroneal retinacular injuries. Subtype A is a pure avulsion of the flexor retinaculum off the medial malleolus. Subtype B is an avulsion of the flexor retinaculum with a rim of bone off the medial malleolus. Type 2: Retinacular teardthis seems to occur in higher energy injuries. Type 3: Deficient retinacular tissue, although no clear trend is available from the published data, this pathologic feature might
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subtype N (normal) or S (shallow). The exact dimensions defining a shallow or normal groove would require a large epidemiologic analysis.
Fig. 8. Groove deepening and retinacular repair. (A) Dislocated tibialis posterior tendon with shallow groove. (B) Tendon relocated in deepened groove and sequential placement of retinacular suture. (C) Relocated tibialis posterior tendon with repaired retinaculum.
occur in cases with long diagnostic delay, medical comorbidities with soft tissue complications, and iatrogenic injury to the flexor retinaculum. Groove modifier: the types and subtypes can be subdivided according to the adequacy of the retromalleolar groove depth as Table 3 Classification and treatment of tibialis posterior dislocation Type
Subtype
Treatment
Groove Modifier, Shallow (S)
1: Avulsion (most common)
A, retinaculum avulsed off medial malleolus B, retinaculum avulsed off medial malleolus with a bony rim None
Transosseous suture repair
Groove deepening
Transosseous suture repair/ possible nonoperative treatment
Groove deepening
Primary repair with sutures Reconstruction with periosteal/ FDL sheath flap
Groove deepening
2: Tear (high energy) 3: Deficient tissue (delayed treatment)
None
Abbreviation: FDL, flexor digitorum longus.
Groove deepening
This broad classification can guide the decision making in the treatment of this pathology. Type 1 should be treated with surgical reduction and transosseous suture or suture anchor repair of the avulsed retinaculum. Whether a type 1B injury would be amenable to closed reduction and immobilization to allow bony healing is not clear and requires further study. Type 2 injuries should be treated with surgical reduction and primary suture repair of the retinacular tear. Type 3 injuries require reconstruction of the retinaculum. The evidence is insufficient to recommend 1 method of reconstruction over another; however, the use of tissue in near proximity, such as periosteal flaps or the FDL tendon sheath, seems sensible. In cases in which the groove is determined to be shallow, a groove deepening procedure should be performed. We recommend our described method, because it preserves the cartilage lining of the retromalleolar groove, thus allowing for smoother tendon gliding and minimizing future adhesions or tendon trauma. This classification system would also allow for more accurate reporting of future cases. The available data have led us to the conclusion that regardless of the pathology and treatment type, the outcome of surgical correction of this condition will almost uniformly be excellent. The inherent deficiency of any standardized outcome measure across a pool of case reports and series might have favorably skewed this perception. Only 1 case of a recurrence after previous surgical correction has been described (11). The application of a validated functional score and a patient-reported outcome score would allow for an objective assessment of individual procedures and their outcomes. For athletes, the time to return to play and at which level is essential information for the treating physician and coaching staff alike and needs careful attention in future reports. In conclusion, TPD has been reported as rare; however, the reported delays in diagnosis could point to many cases having been missed. Patients with persistent medial malleolar pain and swelling after a diagnosis of a sprain should be carefully evaluated for TPD. The reported outcomes for all surgical procedures have been excellent; however, the reports have lacked depth and reproducibility for outcome scores. We have provided a classification system and algorithm to guide the treatment and reporting of future cases.
References 1. Gambardella GV, Donegan R, Caminear DS. Isolated dislocation of the posterior tibial tendon in an amateur snowboarder: a case report. J Foot Ankle Surg 53:203– 207, 2014. 2. Mullens J, Whiteside W, Nilssen E, Kennedy C. Dislocated posterior tibial tendon treated with plate buttress fixation in a collegiate gymnast: a case report and review of the literature. Foot Ankle Spec 9:361–366, 2016. 3. Nava BE. Traumatic dislocation of the tibialis posterior tendon at the ankle: report of a case. J Bone Joint Surg Br 50:150–151, 1968. 4. Al Khudairy A, Zafar MM, Padinjarathala BA. The unexpected with ankle fracture: traumatic tibialis posterior tendon dislocation: a case report and literature review. Foot Ankle Spec 6:482–489, 2013. 5. Biedert R. Dislocation of the tibialis posterior tendon. Am J Sports Med 20:775– 776, 1992. 6. Gambhir AK, Kay PR. Traumatic dislocation of tibialis posterior presenting late as a bony spur. Injury 29:401–402, 1998. 7. Goucher NR, Coughlin MJ, Kristensen RM. Dislocation of the posterior tibial tendon: a literature review and presentation of two cases. Iowa Orthop J 26:122– 126, 2006. 8. Hatori M, Sato H, Kokubun S. Traumatic dislocation of the tibialis posterior tendon. Foot 7:115–117, 1997. 9. Healy WA III, Starkweather KD, Gruber MA. Chronic dislocation of the posterior tibial tendon: a case report. Am J Sports Med 23:776–777, 1995. 10. Langan P, Weiss CA. Subluxation of the tibialis posterior, a complication of tarsal tunnel decompression: a case report. Clin Orthop Relat Res 146:226–227, 1980.
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11. Larsen E, Lauridsen F. Dislocation of the tibialis posterior tendon in two athletes. Am J Sports Med 12:429–430, 1984. 12. Lohrer H, Nauck T. Posterior tibial tendon dislocation: a systematic review of the literature and presentation of a case. Br J Sports Med 44:398–406, 2010. 13. Loncarich DP, Clapper M. Dislocation of posterior tibial tendon. Foot Ankle Int 19:821–824, 1998. 14. Miki T, Kuzuoka K, Kotani H, Ikeda Y. Recurrent dislocation of tibialis posterior tendon: a report of two cases. Arch Orthop Trauma Surg 118:96–98, 1998. 15. Mitchell K, Mencia MM, Hoford R. Tibialis posterior tendon dislocation: a case report. Foot (Edinb) 21:154–156, 2011. 16. Mittal RL, Jain NC. Traumatic dislocation of the tibialis posterior tendon. Int Orthop 12:259–260, 1988. 17. Nuccion SL, Hunter DM, Difiori J. Dislocation of the posterior tibial tendon without disruption of the flexor retinaculum: a case report and review of the literature. Am J Sports Med 29:656–659, 2001. 18. Olive Vilas R, Redon Montojo N, Pino Sorroche S. Traumatic dislocation of tibialis posterior tendon: a case report in a Tae-Kwon-Do athlete. Clin J Sport Med 19:68– 69, 2009. 19. Ouzounian TJ, Myerson MS. Dislocation of the posterior tibial tendon. Foot Ankle 13:215–219, 1992. 20. Perlman MD, Wertheimer SJ, Leveille DW. Traumatic dislocations of the tibialis posterior tendon: a review of the literature and two case reports. J Foot Surg 29:253–259, 1990. 21. Rolf C, Guntner P, Ekenman I, Turan I. Dislocation of the tibialis posterior tendon: diagnosis and treatment. J Foot Ankle Surg 36:63–65, 1997. 22. Sharma R, Jomha NM, Otto DD. Recurrent dislocation of the tibialis posterior tendon. Am J Sports Med 34:1852–1854, 2006. 23. Sharon SM, Knudsen HA, Gastwirth CM. Post-traumatic recurrent subluxation of the tibialis posterior tendon: a case report. J Am Podiatry Assoc 68:500–502, 1978.
24. Soler RR, Gallart Castany FJ, Riba Ferret J, Garcia Ramiro S. Traumatic dislocation of the tibialis posterior tendon at the ankle level. J Trauma 26:1049–1052, 1986. 25. Stanish WD, Vincent N. Recurrent dislocation of the tibialis posterior tendonda case report with a new surgical approach. Can J Appl Sport Sci 9:220–222, 1984. 26. Wong YS. Recurrent dislocation of the posterior tibial tendon secondary to detachment of a retinacular-periosteal sleeve: a case report. Foot Ankle Int 25:602–604, 2004. 27. Roth JA, Taylor WC, Whalen J. Peroneal tendon subluxation: the other lateral ankle injury. Br J Sports Med 44:1047–1053, 2010. 28. Saragas NP, Ferrao PNF, Mayet Z, Eshraghi H. Peroneal tendon dislocation/subluxationdcase series and review of the literature. Foot Ankle Surg 22:125–130, 2016. 29. Eckert WR, Davis EA Jr. Acute rupture of the peroneal retinaculum. J Bone Joint Surg Am 58:670–672, 1976. 30. Heini PF, Ganz R. Anterolateral subluxation of the talus after overlooked dislocation of the tibialis posterior tendon. J Orthop Trauma 8:449–453, 1994. 31. Bencardino J, Rosenberg ZS, Beltran J, Broker M, Cheung Y, Rosemberg LA, Schweitzer M, Hamilton W. MR imaging of dislocation of the posterior tibial tendon. AJR Am J Roentgenol 169:1109–1112, 1997. 32. Kerkhoffs GM, Van Dijk CN. Acute lateral ankle ligament ruptures in the athlete: the role of surgery. Foot Ankle Clin 18:215–218, 2013. 33. Chaudhry H, Simunovic N, Petrisor B. Cochrane in CORR(Ò): surgical versus conservative treatment for acute injuries of the lateral ligament complex of the ankle in adults (review). Clin Orthop Relat Res 473:17–22, 2015. 34. Prato N, Abello E, Martinoli C, Derchi L, Bianchi S. Sonography of posterior tibialis tendon dislocation. J Ultrasound Med 23:701–705, 2004. 35. Lhoste-Trouilloud A. The tibialis posterior tendon. J Ultrasound 15:2–6, 2012.
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Case Reports and Series
Tibialis Posterior Tendon Dislocation: A Review and Suggested Classification Andrew Strydom, MBBCh(Wits), FCOrth(SA), MMed(OrthoSurg) (Wits) 1, 2, Nikiforos Pandelis Saragas, MBBCh(Wits), FCS (SA) Ortho, MMed(OrthoSurg) (Wits) 3, 4, Makgabo Tladi, MBChB(Limpopo), FCOrth(SA) 1, 5, Paulo Norberto Farria Ferrao, MBChB(Pret), FCS (SA) Ortho 2, 6 1
Fellow, The Orthopaedic Foot and Ankle Unit, Netcare Linksfield Hospital, Johannesburg, South Africa Consultant Orthopaedic Surgeon, Department of Orthopaedic Surgery, University of the Witwatersrand, Johannesburg, South Africa 3 Director, The Orthopaedic Foot and Ankle Unit, Netcare Linksfield Hospital, Johannesburg, South Africa 4 Honorary Adjunct Professor, Department of Orthopaedic Surgery, University of the Witwatersrand, Johannesburg, South Africa 5 Consultant Orthopaedic Surgeon, Dr George Mukhari Academic Hospital, Sefako Makgatho Health Science University, Ga-Rankuwa, South Africa 6 Assistant Director, The Orthopaedic Foot and Ankle Unit, Netcare Linksfield Hospital, Johannesburg, South Africa 2
a r t i c l e i n f o
a b s t r a c t
Level of Clinical Evidence: 4
Tibialis posterior tendon dislocation is a rarely described entity that is easily missed, resulting in delayed diagnosis and treatment. A review of the English published data on the topic showed inconsistency in the reporting of injuries and surgical management techniques, leading us to describe a novel classification system to guide treatment and future reporting. We also describe a case of tibialis posterior tendon dislocation in a professional volleyball player and our surgical technique for correction, including retromalleolar groove deepening. Ó 2017 by the American College of Foot and Ankle Surgeons. All rights reserved.
Keywords: classification flexor retinaculum groove deepening retromalleolar groove tendon dislocation tibialis posterior tendon
Tibialis posterior tendon dislocation (TPD) is a relatively rare entity, and the English published data on the topic is limited to case reports and small series (1–26). Since the first description of a traumatic case in 1968 (3), a small, but consistently growing, collection of cases, mostly with a traumatic etiology (1,2,4,7,11,15–18,20,24,26), has emerged. Unlike peroneal tendon injuries, for which the mechanism of injury, association with ankle injuries, diagnostic modalities, and management through surgical stabilization have been well described (27,28), the natural history and treatment guidelines of TPD are unclear. The present study reviewed the available English data, which informs the description of our case management for a professional volleyball player. Systematic Review of the Published Data A summary of the data published in English (including our case) are listed in Tables 1 and 2. A total of 38 cases have been reported from 1968 to 2016, including 20 males (53%) and 18 females (47%). Of the Financial Disclosure: None reported. Conflict of Interest: None reported. Address correspondence to: Andrew Strydom, MBBCh(Wits), FCOrth(SA), MMed(OrthoSurg) (Wits), Orthopaedic Foot and Ankle Unit, Netcare Linksfield Hospital, 24 12th Avenue, Suite 303, Linskfield West, Johannesburg 2193, South Africa. E-mail address: [email protected] (A. Strydom).
38 cases, 27 (71%) occurred before the patient was 40 years old. For 8 cases (21%), the affected side was not reported, 16 cases (53%) were right-sided, and 14 were left-sided (37%). The predominant mechanism of injury involved a foot fixed to the floor with a twisting injury, consisting of forced eversion and dorsiflexion in 28 cases (68%). For the remaining 10 cases, the cause of injury was a high-energy motor vehicle accident in 3, an unclear mechanism in 3, iatrogenic in 2, spontaneous recurrence in 1, and Chopart’s joint dislocation in 1. The prevailing symptom associated with TPD is medial ankle pain, which was present in 29 cases (76%). Persistent swelling was present in 17 cases (45%), and an associated sensation of instability/clicking/ snapping was present in 17 cases (45%) and are other common symptoms. Medial ankle pain combined with persistent swelling and/ or a sensation of instability/clicking/snapping occurred in 24 cases (63%). An inability to weight bear in 3 patients and locking in 1 patient were the only other described symptoms. The posterior tibialis tendon (PTT) was dislocated or dislocatable on physical examination in 23 patients (60%). The interval from injury to surgery was reported for 37 patients (97%); the calculated mean interval to surgery was 17.3 weeks (range 0 to 96). The most common retinacular pathologic feature noted at surgery was anterior avulsion of the flexor retinaculum off the medial
1067-2516/$ - see front matter Ó 2017 by the American College of Foot and Ankle Surgeons. All rights reserved. http://dx.doi.org/10.1053/j.jfas.2017.01.006
2
Table 1 Summary of patient characteristics from a systematic review of data published in English Investigator
Patients (n)
Gender
Age (yr)
Side
Injury Mechanism
Symptoms/Findings
Interval to Surgery (wk)
Swelling
Subluxing Sensation, Snapping, Clicking
Other
PTT Subluxed or Dislocatable at Examination
Yes Yes Yes
NR NR NR
Yes Yes Yes
NR NR NR
Yes Yes No
NR 28 8
Yes Yes
NR NR
NR NR
NR Locking
Yes No
2 5
Yes
NR
Yes
NR
Yes
96
Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes NR Yes
NR NR Yes NR Yes NR Yes Yes Yes NR NR NR
Yes Yes NR NR NR NR Yes Yes NR NR Yes Yes
NR NR NR NR NR NR NR NR NR NR NR NR
Yes Yes Yes No Yes No No Yes No Yes Yes No
0 0 9 1 0 72 4 16 96 2 12 48
Yes
NR
NR
Yes
20
Yes
0
No No No No Yes
2 0 32 24 20
Nava et al (3), 1968 Sharon et al (23), 1978 Langan et al (10), 1980
1 1 1
Male Male Female
16 37 16
Left Right NR
Larsen et al (11), 1984 Recurrent case
2
Male Female
18 36
Left Left
Stanish et al (25), 1984
1
Female
16
Right
Soler et al (24), 1986 Mittal et al (16), 1988 Perlman et al (20), 1990
1 1 2
Biedert (5), 1992 Ouzounian et al (19), 1992
1 7
Male Male Male Male Male Female Female Male Female Male Male Female
39 40 36 27 18 44 17 24 55 42 38 26
Right Left Right Left Right NR NR NR NR NR NR NR
Healy et al (9), 1995
1
Male
14
Right
MVA MVA Iatrogenic, tarsal tunnel release Twist, running Spontaneous recurrence of previously surgically treated dislocation Spontaneous, unclear mechanism Twist, walking Twist, low energy Twist Twist Twist, gymnastics Twist Twist Twist Cortisone injections Twist PER Dislocation of Chopart’s joint Twist, low energy
Hatori et al (8), 1997
1
Female
48
Right
Twist, low-energy squat
Yes
NR
NR
Rolf et al (21), 1997
2
Gambhir et al (6), 1998 Loncarich et al (13), 1998 Miki et al (14), 1998
1 1 2
Male Female Male Male Female
37 53 37 37 41
Left Right Right Left Right
Yes Yes Yes Yes Yes
NR Yes Yes Yes NR
NR Yes NR NR Yes
Nuccion et al (17), 2001 Wong (26), 2004 Goucher et al (7), 2006
1 1 2
Female Male Male Female
41 31 24 27
Right Left Left Left
NR Yes NR Yes
NR Yes NR NR
Yes NR Yes NR
NR NR NR NR
Yes No Yes Yes
4 1 4 28
Sharma et al (22), 2006 Olive Vilas et al (18), 2009 Lohrer et al (12), 2010 Mitchell et al (15), 2011
1 1 1 1
Male Female Female Male Female
37 14 17 57 56
NR Left Right Right Right
Twist, ice skating Twist Twist, cricket (bowling) Twist, rock climbing Twist, low energy, rising from seated Twist, low-energy squat Unclear, sprinting, soccer Playing basketball Twist, running (treated with cortisone injection) Twist, water-skiing Twist, running Twist, Tae-kwon-do Twist, rock climbing Twist, low-energy squat
Unable to bear weight Unable to bear weight NR NR NR NR NR
Yes Yes Yes Yes Yes
NR Yes Yes Yes Yes
NR Yes Yes NR NR
Yes Yes Yes No Yes
1 32 8 28 3
Al Khudairy et al (4), 2013 Gambardella et al (1), 2014 Mullens et al (2), 2015 Present case, 2016
1 1 1 1
Female Male Female Female
17 19 19 41
Left Left Right Right
MVA Unclear, snow boarding Twist, gymnastics Twist, volleyball
Yes Yes Yes Yes
Yes Yes Yes Yes
NR NR NR Yes
NR NR NR NR Unable to bear weight NR NR NR NR
No Yes No Yes
0 28 1 4
Abbreviations: MVA, motor vehicle accident; NR, not reported.
A. Strydom et al. / The Journal of Foot & Ankle Surgery xxx (2017) 1–10
Medial Ankle Pain
Table 2 Summary of pathologic findings from systematic review of data published in English Investigator
Pathologic Findings Groove
Nava et al (3), 1968 Sharon et al (23), 1978
Torn
Langan et al (10), 1980 Larsen et al (11), 1984 Recurrent case Stanish et al (25), 1984 Soler et al (24), 1986 Mittal et al (16), 1988 Perlman et al (20), 1990
Biedert (5), 1992 Ouzounian et al (19), 1992
Healy et al (9), 1995 Hatori et al (8), 1997
Treatment Other
Primary Repair Retinaculum Reconstruction
Immobilization
Normal NR
No
No
Yes
No
10-wk Cast immobilization NR
NR
Shallow NR
No
No
No
5-wk Cast immobilization
Progressive WB from day 5 postoperatively
21
Full recovery
Deficient
Shallow NR
Yes, medial malleolus bone block Yes
No
No
Yes, periosteal flap
Full recovery
NR
NR
No
No
Yes
No
Unlimited walking 4 wk postoperatively NR
36
Torn
4-wk Cast immobilization, WB 6-wk Cast immobilization
12
Full recovery
Avulsion Deficient
NR NR
NR NR
No Yes
Yes, sutures No
No No
No 5-wk Cast immobilization Yes, tenosynovial flap Compressive bandage
36 48
Full recovery Full recovery
Avulsion
Shallow NR
No
Yes, sutures
No
Yes, periosteal flap
3-wk Cast immobilization
NR Progressive WB from day 2 postoperatively 2-wk Physiotherapy
24
Full recovery
Avulsion
NR
No
Yes, sutures
No
No
6
Full recovery
Avulsion, fleck Shallow NR
Yes, bone wedge
Yes, sutures
No
No
3-wk Cast immobilization, plantarflexion 4-wk Cast immobilization
11
Full recovery
Avulsion
Shallow NR
Yes, bone wedge
Yes, sutures
No
No
8-wk Cast immobilization
18
Full recovery
Torn
Normal NR
No
No
Yes, sutures
No
4-wk Night splinting
2,5
Full recovery
Deficient
No Shallow Tendon inflamed with tears
Yes, sutures, No FDL tenodesis
No
4- to 6-wk Cast immobilization
Absent
Normal Tendon inflamed
No
No
No
Yes, deltoid and FDL sheath
4- to 6-wk Cast immobilization
Absent
Shallow NR
No
Yes
No
Yes
4- to 6-wk Cast immobilization
Absent
Normal Inflamed
No
No
No
Yes, periosteum and FDL sheath
4- to 6-wk Cast immobilization
Avulsion Normal NR (bony fleck)
No
Yes, sutures
No
No
4- to 6-wk Cast immobilization
Avulsion Shallow NR (bony fleck)
No
Yes, sutures
No
No
4- to 6-wk Cast immobilization
Deficient
Shallow NR
Yes
Yes, sutures
No
No
4- to 6-wk Cast immobilization
Deficient
Shallow NR
Yes
No
No
Yes, periosteal flap
3-wk Cast immobilization
Avulsion
Normal NR
No
Yes, sutures
No
No
5-wk Cast immobilization
NR
Rehabilitation
Follow-Up Reported (mo) Outcome
Groove Deepening Retinacular Reattachment
NR ROM and progressive WB over 2 wk Progressive WB from 4 wk, then proprioception and strength training NWB 6 wk, then functional rehabilitation Mobilization, strengthening, proprioception until recovery Mobilization, strengthening, proprioception until recovery Mobilization, strengthening, proprioception until recovery Mobilization, strengthening, proprioception until recovery Mobilization, strengthening, proprioception until recovery Mobilization, strengthening, proprioception until recovery Mobilization, strengthening, proprioception until recovery WB from day 1, then 3 wk air brace NR
NR
1
Full recovery
Improved
44
Full recovery
38
Full recovery
32
Occasional symptoms
14
Full recovery
14
Full recovery
16
Full recovery
2
Full recovery
24
Full recovery
3
(continued on next page)
A. Strydom et al. / The Journal of Foot & Ankle Surgery xxx (2017) 1–10
Retinaculum
Investigator
4
Table 2 (continued ) Pathologic Findings
Immobilization
Rehabilitation
Normal NR
No
No
No
Yes, TA strip
6-wk Cast immobilization
Avulsion
Normal NR
No
Yes
No
No
6-wk Cast immobilization
Gambhir et al (6), 1998
Avulsion
Normal Bony spur
No
No
No
None
Loncarich et al (13), 1998 Miki et al (14), 1998
Avulsion
Normal Synovitis
No, tendon decompression and spur excision No
Strength, flexibility, proprioceptive training Strength, flexibility, proprioceptive training Physiotherapy
Yes, sutures
No
No
Deficient
Shallow NR
No
No
No
Physiotherapy, CAM boot for 7 wk NR
Avulsion
Shallow NR
No
No
No
6-wk Cast immobilization
NR
Avulsion
Normal NR
Yes, shelf or bone block Yes, shelf or bone block No
4-wk Cast immobilization, NWB 5-wk Cast immobilization
No
No
6-wk Cast immobilization
Avulsion
NR
No
No
No
Avulsion
Shallow Tears in tendon
Yes
Yes, suture anchors Yes, suture anchors Yes, sutures
No
No
Avulsion Avulsion
NR NR Normal NR
Yes No
Yes, sutures Yes, sutures
No No
No No
Avulsion
Normal NR
No
Yes, sutures
No
No
Avulsion
No
Yes
No
No
Avulsion
Normal Tears in tendon Normal NR
No
Yes, sutures
No
No
Avulsion
NR
No
Yes, sutures and anchor
No
Yes
Yes, sutures
No
Yes
Goucher et al (7), 2006
Sharma et al (22), 2006 Olive Vilas et al (18), 2009 Lohrer et al (12), 2010 Mitchell et al (15), 2011 Al Khudairy et al (4), 2013 Gambardella et al (1), 2014 Mullens et al (2), 2015
Deficient
Avulsion Avulsion
Present case, 2016 Avulsion
Other
NR
Medial malleolus fracture Shallow Tears in tendon Normal Tears in tendon, tibial OCD Shallow Tears in tendon
Physiotherapy, WB as tolerated in CAM boot 4-wk Cast immobilization, Physiotherapy for ROM and inversion, equinus, NWB strengthening Physiotherapy, crossCAM boot, WB at 1 wk training plus ROM, FWB at 6 wk with removable brace NR NR 6-wk Cast immobilization, Physiotherapy, ROM, NWB strengthening, proprioception 5-wk BK cast Functional rehabilitation
Follow-Up Reported (mo) Outcome
12
Full recovery
12
Full recovery
NR
Full recovery
8
Full recovery
144
Full recovery
24
Full recovery
5
Full recovery
11
Full recovery
13
Full recovery
6 12
Full recovery Full recovery
3
Full recovery
6
Full recovery
18
Full recovery
1-wk BK cast, removable splint 6 wk 6-wk cast immobilization
Proprioceptive and strength training NR
No
6-wk NWB cast, PRWB to 12 wk
Progressive WB, active ROM
12
Full recovery
No
No
Physiotherapy, active ROM
12
Full recovery
Yes, buttress plate
No
No
4-wk NWB splint, 2-wk boot, physiotherapy 6-wk NWB cast, boot with PRWB
Physiotherapy, active ROM
12
Full recovery
Yes, sutures
No
No
3
Full recovery
4-wk NWB cast, PRWB in boot
Physiotherapy, ROM, proprioception
Abbreviations: BK, below the knee; CAM, controlled ankle motion; FDL, flexor digitorum longus; NWB, non-weightbearing; NR, not reported; OCD, osteochondritis dissecans; PRWB, partial weightbearing; ROM, range of motion; WB, weightbearing.
A. Strydom et al. / The Journal of Foot & Ankle Surgery xxx (2017) 1–10
Primary Repair Retinaculum Reconstruction
Nuccion et al (17), 2001 Wong (26), 2004
Groove
Treatment Groove Deepening Retinacular Reattachment
Rolf et al (21), 1997
Retinaculum
A. Strydom et al. / The Journal of Foot & Ankle Surgery xxx (2017) 1–10
5
additional report described retinaculum reattachment with a buttress plate in 1 patient. A groove deepening procedure was performed in 13 cases (34%). In 2 patients with a shallow groove, the groove was not deepened, and in 2 cases with no description of the groove depth, the groove depth was deepened. All 3 cases (8%) with a torn retinaculum were managed by primary suturing of the retinaculum. In 10 cases (26%), a deficient retinaculum was reported, with 8 undergoing retinacular reconstruction. In 4 of the reconstruction procedures, a periosteal flap was used. Two cases included a groove deepening procedure. Postoperative cast immobilization was used in 34 cases (89%), with a mean duration of immobilization of 5 weeks (range 1 to 10). In 1 case, the patient was not immobilized at all, 1 patient used a removable night splint, 1 used a compression bandage, and for 1 case, immobilization was not specified. In 27 cases (70%), the patient underwent rehabilitation with physiotherapy exercises of variable quality and purpose. A rehabilitative protocol was not described or the information was unavailable for 11 patients. The functional outcome was reported as full recovery in 36 cases (95%), with a mean final follow-up duration of 19.8 months (range 3 to 144). Also, for 2 patients from the same series improved outcomes with occasional symptoms were reported. Fig. 1. Anteroposterior radiographs showing “fleck sign” (yellow arrow).
Case Report malleolus in 24 cases (63%), followed by a deficient or an absent retinaculum in 10 (26%) and a tear in the substance of the retinaculum in 3 (8%). The status of the retinaculum was not reported for 1 case. The retromalleolar groove was described as shallow in 15 cases (39%). No description was provided regarding the depth of the groove in 6 cases (16%). The associated pathologic features noted at surgery included 6 PTT tears (16%), 4 cases with concomitant inflammation or synovitis (11%), 1 bony spur on the medial malleolus, 1 medial malleolus fracture, and 1 tibial plafond osteochondral defect. The most common surgical procedure performed was retinacular reattachment to the medial malleolus (as described for peroneal tendon subluxation) in 23 cases (61%). In 1 of these cases, a deficient retinaculum was repaired and augmented with a flexor digitorum longus (FDL) tenodesis. In 3 of the cases, suture anchors were used instead of, or in conjunction with, transosseous tunnels. One
We present the case of a 41-year-old healthy professional volleyball player with a history of repeated right ankle injuries and associated instability, in particular, during competitive games. Two weeks before the referral from her physiotherapist, she heard and/or felt a pop over her medial ankle during a volleyball game. The ankle swelled immediately, and she was unable to bear weight on it. This was the most painful injury in her recent memory. She experienced the same symptoms again during evaluation by the physiotherapist with the ankle placed in a position of resisted inversion. She was immobilized in a pneumatic immobilizer boot and referred for further assessment. She was a nonsmoker with no medical comorbidities or allergies. The physical examination revealed a swollen right ankle with a right-sided antalgic gait. She was unable to walk on her toes or heels because of the pain. The right calf and Achilles tendon were soft and not tender. The PTT was tender and boggy on palpation, consistent
Fig. 2. Ultrasound image confirming tibialis posterior dislocation and avulsion of flexor retinaculum with fleck of bone visible.
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A. Strydom et al. / The Journal of Foot & Ankle Surgery xxx (2017) 1–10
Fig. 3. Positioning and surface anatomy.
Fig. 5. Shallow retromalleolar groove.
with associated synovitis. The medial gutter of the ankle, medial malleolus, and deltoid ligaments were moderately tender. The anterior joint line of the ankle was mildly tender. The ankle range of motion was limited owing to pain. Her hindfoot range of motion was normal. Resisted inversion of the foot resulted in obvious and painful dislocation of the PTT over the medial malleolus. The rest of the examination findings were unremarkable, with no neurovascular deficit present. Standard weightbearing radiographs of the ankle were obtained, and careful examination revealed a “fleck sign” on the anteroposterior radiograph at the level of the medial malleolus (Fig. 1). The patient had been previously referred for ultrasound evaluation of the right ankle and foot, which revealed a poorly visualized anterior talofibular ligament and 2 small bony fragments in the deltoid ligament, both consistent with previous injuries. A small ankle effusion was noted. However, the ultrasound report had no comment on the PTT position or quality, necessitating a second ultrasound examination. The second ultrasound examination confirmed the findings of the previous investigation, with the addition of a small (6.2 1.1 4.8 mm) bony fragment, consistent with avulsion of the superior insertion of the medial flexor retinaculum off the medial malleolus (Fig. 2). Dynamic assessment of the PTT confirmed anterior subluxation over the medial malleolus deep to the aforementioned bony fragment. The PTT showed evidence of synovitis and a hypoechoic section of the medial most-fibers at the level of the subluxation,
possibly from early tendinopathy. The flexor hallucis longus, flexor digitorum longus, and peroneal tendons were uninjured. After a discussion of the ultrasound results and treatment options, the patient elected for surgical reconstruction.
Fig. 4. Avulsion of the flexor retinaculum with the subluxed tibialis posterior tendon.
Surgical Procedure The patient was prepared and draped under general anesthesia with a popliteal nerve block, tourniquet, and a bolster under the contralateral hip to facilitate access with the leg in external rotation. The surface anatomy of the medial malleolus, navicular tuberosity, and course of the PTT were drawn using a Codman marker (Fig. 3). The skin incision was continued down to the flexor retinaculum. The retinaculum was then incised over the posterior border of the medial malleolus and was noted to have avulsed from the malleolus with a small bony sleeve (Fig. 4). The tendon itself was synovitic, with multiple small tears. The retromalleolar groove for the PTT was shallow (Fig. 5). We decided to perform a groove deepening procedure. Sequential linear drill holes (1.5-mm drill) were made along the posteromedial and posterolateral border of the medial malleolus for approximately 3 cm. The 2 borders were then connected proximally with drill holes. The drill holes were then connected using a small oscillating saw or sharp osteotome. The bone flap was elevated, with a hinge distally on the tip of the medial malleolus. The underlying cancellous bone was removed using a spine curette to form a void. The outer cortex was returned to its place and carefully impacted into the void. A squareshaped bone punch should preferably be used. This technique maintains the fibrocartilaginous surface of the groove and minimizing adhesion formation (Fig. 6). The tendon was reduced and found to be stable within the deepened groove. All synovitis was debrided. The tendon itself was debrided and repaired with a braided absorbable suture. The medial surface of the medial malleolus is roughened using a rongeur or osteotome to allow the repaired retinaculum to scar down. The PTT was then reduced in its groove and the retinaculum repaired through 3 small drill holes in the posteromedial edge of the malleolus using a braided absorbable suture as demonstrated in Figs. 7 and 8. The tendon was observed to move freely within the retinaculum. The repair site was injected with platelet-rich plasma and the wound was closed in layers. Rehabilitation The foot was immobilized in a below-the-knee non-weightbearing cast for 4 weeks, after which the cast was removed. A pneumatic
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Fig. 6. Groove deepening procedure.
immobilizer boot was fitted for a 2-week period, with progressive weightbearing as tolerated. Physiotherapy was initiated, which consisted of soft tissue mobilization, range of motion, and strengthening and proprioceptive exercises. At 8 weeks, the patient was evaluated again, and the PTT was in a reduced position without any evidence of subluxation during active or resisted movement. The patient only experienced mild discomfort on occasion and had progressed to strengthening exercises under the supervision of the physiotherapist. At 12 weeks postoperatively, the patient was well, with the PTT functioning at normal strength without evidence of subluxation. No evidence of synovitis or tendon injury remained at this point. At 18 months postoperatively, the patient had returned to competing at a national level. Discussion TPD was reported as uncommon in nearly every case report (1–26,29,30); however, our examination of the published data led us to believe that this entity might be more common than previously
thought. Two thirds of the cases reported a twisting force constituting a forced or resisted dorsiflexion-eversion injury (2,5–9,11–22,24), one half of which were sustained during a sporting activity. The published data support the likelihood of this injury occurring in younger patients (31), in particular, those aged <40 years engaging in sporting activity. Ankle injuries are possibly the most common musculoskeletal injuries, particularly in athletes; however, it is most commonly the lateral ligaments that are injured (32,33). Many of the case reports described a significant delay in diagnosis and, ultimately, in treatment (6,7,9,19,22), with an average time to surgery from injury of 17.3 weeks. Thus, we believe the true incidence of TPD might be greater than reported because it can often be overlooked or missed owing to a lack of awareness. With the described symptoms, any patient with persistent medial-sided ankle pain, with or without associated symptoms, should be carefully assessed for a missed TPD. A clearly dislocated or able to be dislocated PTT was evident in 60% of cases; thus, a careful history and examination should allow for a significant increase in diagnostic yield.
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Fig. 7. Tendon repair, reduction and retinacular repair.
For cases in which the diagnosis is still not clear, special investigations are warranted. Plain radiographs allow for the exclusion of most fractures and might reveal a bony avulsion at the level of the medial malleolus, which should raise suspicion for TPD, although this was only reported in 3 cases (19,20). Magnetic resonance imaging allows for study of the PTT position, retinacular injury, and depth of the retromalleolar groove. In 1 report, 100% of cases showed a clear PTT dislocation/subluxation with magnetic resonance imaging (31). Ultrasonography is operator dependent and less reproducible than magnetic resonance imaging but allows for low-cost, effective assessment and dynamic evaluation of the PTT position with an experienced operator (34). The PTT lies within a cartilage-lined retromalleolar groove on the tibia and is stabilized within it by the medial flexor retinaculum (35). This is virtually identical to the anatomic structure of the peroneal tendon groove on the fibula. It is thus reasonable to assume that similar pathologic processes can occur within these structures to produce a TPD. The pathology and classification of peroneal tendon dislocation by Eckert and Davis (29) is well accepted and follows a continuum of injury extent, with grade 1 injuries occurring more commonly than grade 3. The major pathology in TPD is insufficiency of the flexor retinaculum to contain the tendon, either in the form of torn or redundant tissue or avulsion of the anterior retinaculum off the medial malleolus. Similar to the peroneal side pathology, a bony avulsion of the retinaculum off the medial malleolus is less common, and was
reported in 4 cases (19,20). It is possible that this type of injury might be more common than reported; thus, radiographs must be carefully assessed for a “fleck sign,” because this subgroup might be amenable to nonoperative management. A shallow retromalleolar groove might increase the risk of peroneal tendon dislocation (28), and the same might be true for TPD. A groove deepening procedure, either in the form of burring away bone or functionally deepening the groove with a bony block/shelf-type procedure, was described in 7 cases, in conjunction with a retinacular procedure. Of the 3 patients without a groove deepening procedure, 2 were reported to have a full functional recovery (19,24) and 1 had residual symptoms (19). In contrast, all the patients who had undergone a groove deepening were reported to have full recovery. Using the available data, we suggest the following classification and treatment algorithm based on the type of retinacular pathology and depth of the retromalleolar groove (Table 3): Type 1: Avulsion injury (most common), with subtypes A and B, similar to the description by Eckert and Davis (29) for peroneal retinacular injuries. Subtype A is a pure avulsion of the flexor retinaculum off the medial malleolus. Subtype B is an avulsion of the flexor retinaculum with a rim of bone off the medial malleolus. Type 2: Retinacular teardthis seems to occur in higher energy injuries. Type 3: Deficient retinacular tissue, although no clear trend is available from the published data, this pathologic feature might
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subtype N (normal) or S (shallow). The exact dimensions defining a shallow or normal groove would require a large epidemiologic analysis.
Fig. 8. Groove deepening and retinacular repair. (A) Dislocated tibialis posterior tendon with shallow groove. (B) Tendon relocated in deepened groove and sequential placement of retinacular suture. (C) Relocated tibialis posterior tendon with repaired retinaculum.
occur in cases with long diagnostic delay, medical comorbidities with soft tissue complications, and iatrogenic injury to the flexor retinaculum. Groove modifier: the types and subtypes can be subdivided according to the adequacy of the retromalleolar groove depth as Table 3 Classification and treatment of tibialis posterior dislocation Type
Subtype
Treatment
Groove Modifier, Shallow (S)
1: Avulsion (most common)
A, retinaculum avulsed off medial malleolus B, retinaculum avulsed off medial malleolus with a bony rim None
Transosseous suture repair
Groove deepening
Transosseous suture repair/ possible nonoperative treatment
Groove deepening
Primary repair with sutures Reconstruction with periosteal/ FDL sheath flap
Groove deepening
2: Tear (high energy) 3: Deficient tissue (delayed treatment)
None
Abbreviation: FDL, flexor digitorum longus.
Groove deepening
This broad classification can guide the decision making in the treatment of this pathology. Type 1 should be treated with surgical reduction and transosseous suture or suture anchor repair of the avulsed retinaculum. Whether a type 1B injury would be amenable to closed reduction and immobilization to allow bony healing is not clear and requires further study. Type 2 injuries should be treated with surgical reduction and primary suture repair of the retinacular tear. Type 3 injuries require reconstruction of the retinaculum. The evidence is insufficient to recommend 1 method of reconstruction over another; however, the use of tissue in near proximity, such as periosteal flaps or the FDL tendon sheath, seems sensible. In cases in which the groove is determined to be shallow, a groove deepening procedure should be performed. We recommend our described method, because it preserves the cartilage lining of the retromalleolar groove, thus allowing for smoother tendon gliding and minimizing future adhesions or tendon trauma. This classification system would also allow for more accurate reporting of future cases. The available data have led us to the conclusion that regardless of the pathology and treatment type, the outcome of surgical correction of this condition will almost uniformly be excellent. The inherent deficiency of any standardized outcome measure across a pool of case reports and series might have favorably skewed this perception. Only 1 case of a recurrence after previous surgical correction has been described (11). The application of a validated functional score and a patient-reported outcome score would allow for an objective assessment of individual procedures and their outcomes. For athletes, the time to return to play and at which level is essential information for the treating physician and coaching staff alike and needs careful attention in future reports. In conclusion, TPD has been reported as rare; however, the reported delays in diagnosis could point to many cases having been missed. Patients with persistent medial malleolar pain and swelling after a diagnosis of a sprain should be carefully evaluated for TPD. The reported outcomes for all surgical procedures have been excellent; however, the reports have lacked depth and reproducibility for outcome scores. We have provided a classification system and algorithm to guide the treatment and reporting of future cases.
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