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Retrotalar fat impingement: an old concept, a new idea
The Foot (1997) 7, 97-100 0 1997 Pearson Professmnal Ltd
Retrotalar fat impingement: an old concept, a new idea M. Heim,* I. Siev-Ner,* M. Huszar,+S. Engelberg,’F. Rottenberg,’ M. Azaria* *Department of Orthopaedic Rehabilitation and TDepartment of Pathology, The Chaim SXeba Medical Center; Tel Aviv University, Israel and IPodiatrist, New York, Nx USA
The study comprised of 10 patients (nine ballet-dancers and one athelete) who underwent excision of the OStrigonum, due to pain on full plantar-flexion. In each case, at surgery the retrotalar fat appeared to be under pressure and bulged through the incision site. Histological examination revealed extensive fibrosis of this fat. It is postulated, therefore, that impingement had occurred between the posterior lip of the tibia and the plantar flexed calcaneum. A subsequent ballet-dancer (not included in the nine), who experienced retrotibial pain, had no OStrigonum and whose bone scan was positive, underwent simple adipose tissue excision, with equally good results. A similarity is noted with Hoffa’s syndrome and the question has arisen as to whether it is necessary to excise the OStrigonum or whether removal of the fat pad alone will suffice. SUMMARY
INTRODUCTION
The concept of intra-articular fat impingement was described by Hoffal in 1904. Other eminent surgeons, such as Smillie,‘Metheny and Major,3 confirmed the pathological entity and collectively agreed that fat pad excision provides sastisfactory results. This traumatized, painful, symptomatic and intraarticular adipose pathology has been termed ‘Hoffa’s syndrome’. It is proposed by the authors that the same pathogenesis occurs within the adipose tissue situated extra-articularly between the posterior aspect of the tibia and the Achilles’ tendon. In symptomatic ballet-dancers and others, where an OStrigonum has been noted on X-ray examination, and where conservative management has failed to relieve the symptoms, surgery to remove the OS trigonum has been recommended. Invariably, a hypertrophic fat pad has been noted at surgery. One questions whether excision of the fat pad alone would suffice.
MATERIALS
Fig. l-Fat
pad clearly
seen to be bulging
through
the mclsion
site.
patients had previously been treated conservatively; their orthopaedic management having included rest, non-steroidal anti-inflammatory drugs and various modalities of physiotherapy. Despite this therapy, there had been no improvement. In each patient an OStrigonum was noted on X-ray examination and an isotope bone scan with technetium (Tcm) proved positive. Surgery was performed under local anaesthesia, through a lateral approach. In all cases, it was noted that the retro-talar area contained an exceptionally large quantity of adipose tissue. The bulbous fatty tissue was excised, thus exposing the OStrigonum and facilitating its excision. Being under pressure, the fat bulged through the incision as soon as the area was exposed (Fig. 1). In each case, the excised fat and bone were sent for histological examination. Histology shows areas of fibrosis with the normal fat (Fig. 2) and fibrosis within the
AND METHODS
Nine ballet-dancers and one athlete underwent surgery for removal of the OS trigonum. All the
Correspondence to Professor Michael Heim, MB, ChB, Department of Orthopaedic Rehabilitation, The Chaim Sheba Medical Center, Tel Hashomer, 52621, Israel. Tel: 00 972 3 5303702. Fax. 00 972 3 5355944.
97
98
The Foot
Fig. 2--The haemotoxylon
Fig. &The
extra-articular and eosin;
fat demonstrates fibrosis magnification: 1x100).
within
histological section shows torn degenerative of the OS trigonum. Extensive fibrosis is evident (stain: haemotoxylon and eosin: magnification: 1x25).
(stain:
Fig. SExtensive haemotoxylon
cartilage
fibrosis and eosin;
Fig. 5-Lateral
X-ray
within the synovial membrane magnification: 1x25).
of the ankle joint,
showing
(stain:
no OS trlgonum.
DISCUSSION
synovial membrane (Fig. 3). The OS trigonum itself demonstrates chondrosis of the articular surface, tears in the cartilage and fibrosis (Fig. 4). An eleventh patient, a 22-year-old ballet-dancer, suffered from ankle pain on forced plantar flexion. No OStrigonum was evident on X-ray examination (Fig. 5) and a Tcm bone scan was positive, indicating retrotibia1 pathology (Fig. 6A-B). At surgery, only the retro-articular fat pad was removed (Fig. 7A-B).
RESULTS
On the first postoperative day, the patients were encouraged to actively move their ankle joints. Within 3 days, active and assisted-active exercises were prescribed, with emphasis being placed on the achievement of a maximum range of movements. Within weeks, the ballet-dancers had returned to active training and performing, all had maintained their range of movements and two had even improved the pointe position. The only failure was the athlete, whose range of ankle dorsiflexion remained limited, preventing him from running. Apart from this patient, the remainder of the group are asymptomatic.
In 1904, Hoffa described the presence of an adipose structure in the anterior portion of the knee joint.’ Symptoms attributed to knee pathology and related to this fatty structure have been grouped together and collectively referred to as Hoffa’s syndrome.4 The clinical manifestations of pain and swelling have been linked with recurrent impingement of the fat pad, a process which results in changes within the fat pad itself. Diagnostic techniques to determine pathology within the fat pad have been described, and range from arthroscopy,4 to sonography5 and to magnetic resonance imaging (MRI).” If this normal, intra-articular structure can cause pain within the functioning joint and be clinically classified as a cause of internal derangement of the knee, the possibility could exist that in other areas of the body a fatty structure may cause a similar pathological entity. It is proposed that such an entity exists, not as an intraarticular fatty body, but rather as an extra-articular adipose mass which, due to excessive ankle movements, becomes impinged. Ballet-dancers and athletes who develop excessive plantar flexion of the ankle joint, develop pain behind this joint. This pathology is frequently recognized in ballet-dancers7,8 where the ankle joint is
Retrotalar fat impingement
R Fig. &(A)
99
6 Bone scan of the ankle joint:
anterior-posterior
view. (B) Bone scan of the ankle jomt:
lateral
view
Fig. 7-(A) Histological section (stain: haemotoxylon and eosin; magnification: 1x100) showing normal adipose tissue m the upper-right corner. and adipose tissue along the bottom, skirted by a synovial membrane. The tissues between the two fat masses show extensive fibrosis. (B) An enlarged section of the central portion of Fig. 7A, clearly showing the fibrosis m relation to the adipose tissues.
forced into plantar flexion for the pointe and demipointe positions. During plantar flexion of the ankle joint, the posterior portion of the calcaneum is drawn upwards, applying pressure to the posterior portion of the talus. Various theories have been proposed with regard to the aetiology of the pain from the posterior portion of the talus and the OStrigonumeg Nevertheless, whichever theory is considered as correct, the fact remains that the posterior portion of the talus becomes compressed between the posterior distal aspect of the tibia and the raising calcaneous. One author has described this as a ‘nut in a nutcracker’.” After conservative therapy has failed to alleviate the pain caused by plantar flexion, surgery is recommended. The operation, performed either by way of a
medial or lateral approach, facilitates access to the posterior portion of the talus. It is the experience of the authors that in each patient undergoing this surgical procedure, a large quantity of fat is present in the area and, furthermore, is under pressure. The presence of adipose tissue in this area has been described as normal.” The presence of fibrosis within the histological sections indicates that damage has occurred to this fatty tissue and, furthermore, that removal of this fat pad alone has relieved the symptoms. Histological examination of the articular surface of the OStrigonum has proved unequivocally that damage has been caused to the articular cartilage. Does this indicate that the OStrigonum should be removed? Similar pathology is noted in chondromalacia patellae. However, patellectomy is not freely advocated.
100
The Foot
Removal of the OStrigonum involves incision into the posterior joint capsule. Capsular repair inevitably results in shortening, which limits dorsiflexion (this occurred in one patient in this series). The arthrotomy increases the morbidity. One should bear in mind that the symptoms of posterior ankle joint pain may exist without evidence of an OS trigonum, and this further enhances the assumption of a problematic fat pad. The authors of this study believe that histologically demonstrated reparative fibrosis within the retrotalar fat pad unequivocally indicates that this tissue has been traumatized.
REFERENCES
1. Hoffa A. Influence of adipose tissue with regard to the pathology of the kneeJoint. JAMA 1904; 43: 795-796. 2. Smillie I S. Lesions of the infra patella fat pad and synovial fringes: Hoffa’s disease. Acta Orthop Stand 1963; 33: 371-377.
3. Metheny J A, Major M B. Hoffa Disease: Chronic impingement of the infra-patella fat pad. Am J Knee Surg 1988; 1: 134139. 4. Magi M, Barca A, Bucca C, Langerance V. Hoffa Disease. Ital J Orthop Traumatoll991; 17: 211-216. 5. Morvay Z, Csokasi Z. Anatomical basis of ultrasonography of the knee. Magy Traumatol Prthop Helyrallito Sebesz 1991; 34: 175-180. 6. Schweitzer M E, Falk A, Pathria M, Brahme S, Hodle J, Resnick D. MR imaging of the knee: Can changes in the intra capsular fat pad be used as a sign of synovial proliferation in the presence of an effusion? AJR 1993; 160: 8233826. 7. Ryan A J, Stephens R E. Dance Medicine. Chicago, Plunibus Press Inc. 1987: 119-134. 8. Howse J, Hancock S. Dance Technique and Injury Prevention 2nd edn. A C Black, London. 1992: 114115. 9. Heim M, Blankstein A, Amit Y, Horoszowski H. Case study: Persistent ankle pain - The OStrigonum duly considered. JOSPT 1987; 8: 402404. 10. Hedrick M R, McBryde A M. Posterior ankle impingement. Foot&Ankle 1994; 15: 2-8. 11. Davies D, Davies F. Grays Anatomy. 33rd Edition. London, Longmans Group and Co Ltd. 1962: 711.
Retrotalar fat impingement: an old concept, a new idea M. Heim,* I. Siev-Ner,* M. Huszar,+S. Engelberg,’F. Rottenberg,’ M. Azaria* *Department of Orthopaedic Rehabilitation and TDepartment of Pathology, The Chaim SXeba Medical Center; Tel Aviv University, Israel and IPodiatrist, New York, Nx USA
The study comprised of 10 patients (nine ballet-dancers and one athelete) who underwent excision of the OStrigonum, due to pain on full plantar-flexion. In each case, at surgery the retrotalar fat appeared to be under pressure and bulged through the incision site. Histological examination revealed extensive fibrosis of this fat. It is postulated, therefore, that impingement had occurred between the posterior lip of the tibia and the plantar flexed calcaneum. A subsequent ballet-dancer (not included in the nine), who experienced retrotibial pain, had no OStrigonum and whose bone scan was positive, underwent simple adipose tissue excision, with equally good results. A similarity is noted with Hoffa’s syndrome and the question has arisen as to whether it is necessary to excise the OStrigonum or whether removal of the fat pad alone will suffice. SUMMARY
INTRODUCTION
The concept of intra-articular fat impingement was described by Hoffal in 1904. Other eminent surgeons, such as Smillie,‘Metheny and Major,3 confirmed the pathological entity and collectively agreed that fat pad excision provides sastisfactory results. This traumatized, painful, symptomatic and intraarticular adipose pathology has been termed ‘Hoffa’s syndrome’. It is proposed by the authors that the same pathogenesis occurs within the adipose tissue situated extra-articularly between the posterior aspect of the tibia and the Achilles’ tendon. In symptomatic ballet-dancers and others, where an OStrigonum has been noted on X-ray examination, and where conservative management has failed to relieve the symptoms, surgery to remove the OS trigonum has been recommended. Invariably, a hypertrophic fat pad has been noted at surgery. One questions whether excision of the fat pad alone would suffice.
MATERIALS
Fig. l-Fat
pad clearly
seen to be bulging
through
the mclsion
site.
patients had previously been treated conservatively; their orthopaedic management having included rest, non-steroidal anti-inflammatory drugs and various modalities of physiotherapy. Despite this therapy, there had been no improvement. In each patient an OStrigonum was noted on X-ray examination and an isotope bone scan with technetium (Tcm) proved positive. Surgery was performed under local anaesthesia, through a lateral approach. In all cases, it was noted that the retro-talar area contained an exceptionally large quantity of adipose tissue. The bulbous fatty tissue was excised, thus exposing the OStrigonum and facilitating its excision. Being under pressure, the fat bulged through the incision as soon as the area was exposed (Fig. 1). In each case, the excised fat and bone were sent for histological examination. Histology shows areas of fibrosis with the normal fat (Fig. 2) and fibrosis within the
AND METHODS
Nine ballet-dancers and one athlete underwent surgery for removal of the OS trigonum. All the
Correspondence to Professor Michael Heim, MB, ChB, Department of Orthopaedic Rehabilitation, The Chaim Sheba Medical Center, Tel Hashomer, 52621, Israel. Tel: 00 972 3 5303702. Fax. 00 972 3 5355944.
97
98
The Foot
Fig. 2--The haemotoxylon
Fig. &The
extra-articular and eosin;
fat demonstrates fibrosis magnification: 1x100).
within
histological section shows torn degenerative of the OS trigonum. Extensive fibrosis is evident (stain: haemotoxylon and eosin: magnification: 1x25).
(stain:
Fig. SExtensive haemotoxylon
cartilage
fibrosis and eosin;
Fig. 5-Lateral
X-ray
within the synovial membrane magnification: 1x25).
of the ankle joint,
showing
(stain:
no OS trlgonum.
DISCUSSION
synovial membrane (Fig. 3). The OS trigonum itself demonstrates chondrosis of the articular surface, tears in the cartilage and fibrosis (Fig. 4). An eleventh patient, a 22-year-old ballet-dancer, suffered from ankle pain on forced plantar flexion. No OStrigonum was evident on X-ray examination (Fig. 5) and a Tcm bone scan was positive, indicating retrotibia1 pathology (Fig. 6A-B). At surgery, only the retro-articular fat pad was removed (Fig. 7A-B).
RESULTS
On the first postoperative day, the patients were encouraged to actively move their ankle joints. Within 3 days, active and assisted-active exercises were prescribed, with emphasis being placed on the achievement of a maximum range of movements. Within weeks, the ballet-dancers had returned to active training and performing, all had maintained their range of movements and two had even improved the pointe position. The only failure was the athlete, whose range of ankle dorsiflexion remained limited, preventing him from running. Apart from this patient, the remainder of the group are asymptomatic.
In 1904, Hoffa described the presence of an adipose structure in the anterior portion of the knee joint.’ Symptoms attributed to knee pathology and related to this fatty structure have been grouped together and collectively referred to as Hoffa’s syndrome.4 The clinical manifestations of pain and swelling have been linked with recurrent impingement of the fat pad, a process which results in changes within the fat pad itself. Diagnostic techniques to determine pathology within the fat pad have been described, and range from arthroscopy,4 to sonography5 and to magnetic resonance imaging (MRI).” If this normal, intra-articular structure can cause pain within the functioning joint and be clinically classified as a cause of internal derangement of the knee, the possibility could exist that in other areas of the body a fatty structure may cause a similar pathological entity. It is proposed that such an entity exists, not as an intraarticular fatty body, but rather as an extra-articular adipose mass which, due to excessive ankle movements, becomes impinged. Ballet-dancers and athletes who develop excessive plantar flexion of the ankle joint, develop pain behind this joint. This pathology is frequently recognized in ballet-dancers7,8 where the ankle joint is
Retrotalar fat impingement
R Fig. &(A)
99
6 Bone scan of the ankle joint:
anterior-posterior
view. (B) Bone scan of the ankle jomt:
lateral
view
Fig. 7-(A) Histological section (stain: haemotoxylon and eosin; magnification: 1x100) showing normal adipose tissue m the upper-right corner. and adipose tissue along the bottom, skirted by a synovial membrane. The tissues between the two fat masses show extensive fibrosis. (B) An enlarged section of the central portion of Fig. 7A, clearly showing the fibrosis m relation to the adipose tissues.
forced into plantar flexion for the pointe and demipointe positions. During plantar flexion of the ankle joint, the posterior portion of the calcaneum is drawn upwards, applying pressure to the posterior portion of the talus. Various theories have been proposed with regard to the aetiology of the pain from the posterior portion of the talus and the OStrigonumeg Nevertheless, whichever theory is considered as correct, the fact remains that the posterior portion of the talus becomes compressed between the posterior distal aspect of the tibia and the raising calcaneous. One author has described this as a ‘nut in a nutcracker’.” After conservative therapy has failed to alleviate the pain caused by plantar flexion, surgery is recommended. The operation, performed either by way of a
medial or lateral approach, facilitates access to the posterior portion of the talus. It is the experience of the authors that in each patient undergoing this surgical procedure, a large quantity of fat is present in the area and, furthermore, is under pressure. The presence of adipose tissue in this area has been described as normal.” The presence of fibrosis within the histological sections indicates that damage has occurred to this fatty tissue and, furthermore, that removal of this fat pad alone has relieved the symptoms. Histological examination of the articular surface of the OStrigonum has proved unequivocally that damage has been caused to the articular cartilage. Does this indicate that the OStrigonum should be removed? Similar pathology is noted in chondromalacia patellae. However, patellectomy is not freely advocated.
100
The Foot
Removal of the OStrigonum involves incision into the posterior joint capsule. Capsular repair inevitably results in shortening, which limits dorsiflexion (this occurred in one patient in this series). The arthrotomy increases the morbidity. One should bear in mind that the symptoms of posterior ankle joint pain may exist without evidence of an OS trigonum, and this further enhances the assumption of a problematic fat pad. The authors of this study believe that histologically demonstrated reparative fibrosis within the retrotalar fat pad unequivocally indicates that this tissue has been traumatized.
REFERENCES
1. Hoffa A. Influence of adipose tissue with regard to the pathology of the kneeJoint. JAMA 1904; 43: 795-796. 2. Smillie I S. Lesions of the infra patella fat pad and synovial fringes: Hoffa’s disease. Acta Orthop Stand 1963; 33: 371-377.
3. Metheny J A, Major M B. Hoffa Disease: Chronic impingement of the infra-patella fat pad. Am J Knee Surg 1988; 1: 134139. 4. Magi M, Barca A, Bucca C, Langerance V. Hoffa Disease. Ital J Orthop Traumatoll991; 17: 211-216. 5. Morvay Z, Csokasi Z. Anatomical basis of ultrasonography of the knee. Magy Traumatol Prthop Helyrallito Sebesz 1991; 34: 175-180. 6. Schweitzer M E, Falk A, Pathria M, Brahme S, Hodle J, Resnick D. MR imaging of the knee: Can changes in the intra capsular fat pad be used as a sign of synovial proliferation in the presence of an effusion? AJR 1993; 160: 8233826. 7. Ryan A J, Stephens R E. Dance Medicine. Chicago, Plunibus Press Inc. 1987: 119-134. 8. Howse J, Hancock S. Dance Technique and Injury Prevention 2nd edn. A C Black, London. 1992: 114115. 9. Heim M, Blankstein A, Amit Y, Horoszowski H. Case study: Persistent ankle pain - The OStrigonum duly considered. JOSPT 1987; 8: 402404. 10. Hedrick M R, McBryde A M. Posterior ankle impingement. Foot&Ankle 1994; 15: 2-8. 11. Davies D, Davies F. Grays Anatomy. 33rd Edition. London, Longmans Group and Co Ltd. 1962: 711.