Treatment of supracondylar femoral fracture above total knee replacement by custom made hinged prosthesis

Treatment of supracondylar femoral fracture above total knee replacement by custom made hinged prosthesis

The Knee 7 Ž2000. 165᎐170 Original article Treatment of supracondylar femoral fracture above total knee replacement by custom made hinged prosthesis...

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The Knee 7 Ž2000. 165᎐170

Original article

Treatment of supracondylar femoral fracture above total knee replacement by custom made hinged prosthesis J. KeenanU , G. Chakrabarty, J.H. Newman A¨ on Orthopaedic Centre, Southmead Hospital, Westbury on Trym, Bristol BSIO 5NB, UK Received 1 February 2000; accepted 31 March 2000

Abstract A supracondylar fracture above a total knee arthroplasty ŽTKA. is a devastating complication for both the patient and surgeon. Various methods of treatment are available. We have treated seven cases of displaced supracondylar fractures above a total knee replacement with custom made implants. This technique allows rapid post-operative recovery and gives a good functional outcome. 䊚 2000 Elsevier Science B.V. All rights reserved. Keywords: Total knee arthroplasty; Supracondylar femoral fracture; Custom made prosthesis

1. Introduction A supracondylar fracture of the femur following a total knee replacement is a recognised, serious, late complication with a reported incidence of between 0.5 and 2.5% w1᎐3x. Various methods of treatment have been employed. Some authors advocate initial conservative treatment, particularly in undisplaced and minimally displaced fractures, with open reduction and internal fixation being employed only after the failure of the initial conservative treatment w3᎐5x. Others have recommended early primary internal fixation for all supracondylar fractures above a total knee arthroplasty ŽTKA., reporting complication rates of only 10᎐19% with surgery w6,7x. Other authors reserve internal fixation for displaced supracondylar fractures w8x. Although most supracondylar fractures can be internally fixed, this may be difficult if the bone is extremely porotic or the fracture very low. Good U

Corresponding author. The Old Estate House, South Town, Kenton, Devon, EX6 8JE. Tel.: q44-1626-890637.

results have been reported using a supracondylar nail w9x, but even this may be impossible if there is insufficient distal bone or if a stabilised prosthesis has been used. In such circumstances, revision of a customised prosthesis can provide the solution. In this paper, we wish to report our experience of managing seven patients in this way.

2. Patients and methods From January 1994 to August 1996, six women and one man were treated for a supracondylar femoral fracture above a previously inserted total knee replacement ŽTable 1.. The average age of the patients was 78 years Žrange 69᎐87 years. and their average weight was 90 kg Žrange 70᎐120 kg.. The prostheses had been in situ for between 4 weeks and 14 years. The prostheses replaced were five Kinematic, one PFC and one Lubinus patellofemoral replacement. Six fractured after a fall, but one patient ŽCase 5. fractured during normal walking, in association with notching of the femur. Two patients had primary internal fixation of the

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Table 1 Patients with supracondylar fracture of the knee after total knee arthroplasty treated with a custom made prosthesis Age

Sex

Weight

Prosthesis replaced

Time from arthroplasty

Fracture type

Initial treatment

No. 1

72 years

F

109 kg

Kinematic

7 years

Displaced

No. 2

72 years

M

120 kg

Kinematic

7 years

Displaced

No. 3

84 years

F

88 kg

Kinematic

5 years

Displaced

No. 4

69 years

F

85 kg

18 months

Displaced comminuted

No. 5

80 years

F

75 kg

Lubinus patellofemoral PFC

Internal fixation and bone graft. Unstable at 8 weeks Open reduction, Steinman pin fixation and cast brace Internal fixation. Non union and implant failure Skin traction

4 weeks

Displaced

No. 6 No. 7

79 years 87 years

F F

72 kg 86 kg

Kinematic Kinematic

14 years 6 years

Comminuted Displaced

Thomas splintrback slab Cylinder Traction

Post op. time to independent mobilisation using aids. 7 days

Post-op. time to discharge

Length of review

Post-op. range of movement

Post-op. Bristol knee score

3 weeks

2.5 years

0᎐100

78 good

3 weeks

4 months

0᎐70 subsequent infection required revision

NrA

7 days

4 weeks

2 years

0᎐90

83 good

7 days

2 weeks

13 months

0᎐105

81 good

7 days

3 weeks

4 months

0᎐105

89 excellent

2 weeks 10 weeks

3 weeks 2 weeks

6 months 6 months

0᎐90 0᎐90

75 good 75 good

10 days

J. Keenan et al. r The Knee 7 (2000) 165᎐170

Case

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with the femoral component, was removed after resecting the femur through the predetermined site. If, at operation, it was felt that resecting less of the femur would be adequate, then this was done accordingly, as the prosthesis design could accommodate the adjustment. The tibial component was then removed as in a standard revision procedure, preserving as much bone as possible. The spacers were selected for the correct length, cemented to each other and then to the femur and tibia. Post-operatively, a normal rehabilitation regime was followed as for a primary knee arthroplasty. Mobilisation was commenced on the first post-operative day, with active physiotherapy and occupational therapy. Our patients were assessed post-operatively using the Bristol Knee Score.

Fig. 1. Ža. Custom endo-rotating knee prosthesis with 5-mm polyethylene spacer doughnut rings ᎏ anteroposterior view; Žb. custom endo-rotating knee prosthesis with 5-mm polyethylene spacer doughnut rings ᎏ lateral view.

fracture which failed with a non-union at the fracture site. One patient had a tibial Steinman pin inserted for skeletal traction after an open reduction. He subsequently developed a pin track abscess, which was aggressively treated with debridement surgery and antibiotics, with apparent complete clinical resolution but with a persistent non-union at the fracture site. It was elected to treat the remaining four patients with revision arthroplasty since the fracture was deemed unfixable and they were temporarily immobilised whilst the prosthesis was manufactured. All patients were treated with a long-stem custommade hinged endoprosthesis ŽWaldemarLink, GmbH, Hamburg, Germany.. A hinged prosthesis was deemed necessary because femoral condyles and collateral ligaments were being sacrificed due to the nature of the injury. The customised endo-rotating knee was selected because of its proven track record and its ability to accommodate a slightly unpredictable level of bone resection. The prosthesis had multiple 5-mm polyethylene spacer doughnut rings surrounding the stem ŽFig. 1. to allow fine adjustment of the prosthesis length, joint line and tissue tension at the time of surgery. Full length measurement radiographs of both legs were sent to the engineers to enable prosthesis manufacture. The process took approximately 3 weeks from ordering to final delivery. The level of resection of the distal femur was decided at pre operative planning. The knee was exposed through the previous scar, using the most lateral where multiple scars were present. The patella was dislocated where possible. The distal femur, along

3. Illustrative cases 3.1. Case no 3 A short, 88 kg, 84-year-old lady had done well following a Kinematic ŽHowmedica, Newbury, Berkshire, UK. knee replacement 5 years previously. A minor fall resulted in a fracture above the prosthesis. This was internally fixed, and the leg protected in a brace. After 5 months the fixation had clearly failed ŽFig. 2. and the patient remained immobile. A customised endo-rotating hinge was inserted. The patient was a poor rehabilitation prospect, but none the less was walking a little after 7 days and was discharged after 4 weeks. When reviewed 13 months later, she was pain free and had regained her preinjury mobility. Radiologically, the prosthesis appeared satisfactory ŽFig. 3.. 3.2. Case no 5 A PFC ŽJohnson and Johnson, Raynham, MA, USA. modular knee replacement had been used to treat tricompartmental osteoarthritis in an 80-year-old lady with mild Parkinsons Disease. Notching of the femur was noted post-operatively ŽFig. 4.. She made a good post-operative recovery, with improved mobility. Four weeks later, she tripped and fell, landing on her left knee sustaining a displaced supracondylar fracture of the femur, just proximal to the implant ŽFig. 5.. She was initially treated with skin traction, full-length radiographs were taken of both legs and the custom-made implant was ordered. A revision operation using the custom made implant was performed exactly 4 weeks after the fall ŽFig. 6.. She made an excellent post-operative recovery, and was discharged home after 3 weeks. At the latest assessment Ž4 months., she has no pain and is

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J. Keenan et al. r The Knee 7 (2000) 165᎐170

Fig. 2. Ža. Case 3: periprosthetic fracture above kinematic total knee replacement ᎏ anteroposterior radiograph; Žb. Case 3: periprosthetic fracture above kinematic total knee replacement ᎏ lateral radiograph; Žc. Case 3: failed open reduction and internal fixation of periprosthetic fracture above kinematic total knee replacement ᎏ anteroposterior radiograph.

able to walk for between 10 and 30 min without any aids on a stable knee with a range of movement of 0᎐105⬚. This gives her a good quality of life. 4. Results (see Table 1) The average follow-up in these patients was 12 months Ža range of 4 months to 2 years.. All patients made a rapid post-operative recovery, being mobile with the use of simple walking aids after 7 days, and discharged from hospital, on average, 3 weeks after surgery. Unfortunately the patient who had a tibial pin inserted pre-operatively developed recurrent deep sepsis, requiring the subsequent removal of the prosthesis. At the latest assessment, the six remaining patients have all had a good or excellent outcome as measured by the Bristol Knee Score.

satisfactory results in 83% of patients w11x. This is comparable to that found in patients without a knee prosthesis w12x. In some other small series, satisfactory results from non-operative treatments are also quoted w4,8x. However, conservative treatment involves a prolonged period of knee immobilisation w3x and is associated with risks of deep venous thrombosis, pulmonary embolism, pressure sores, psychological deterioration and other complications w11x. In unstable or displaced supracondylar fractures,

5. Discussion A supracondylar fracture above a TKA presents a difficult problem. To maintain good function from the arthroplasty, anatomical fracture alignment with the maintenance of component fixation and a range of movement to 90⬚ is required w10x. Ideally, this should be obtained rapidly, but these goals are difficult to achieve particularly in an elderly group of patients with porotic bone, often with concomittant pathologies, and poor pre-injury mobility. In stable, undisplaced or minimally displaced supracondylar fractures, conservative techniques may yield

Fig. 3. Ža. Case 3: 13 months after revision to custom endo-rotating knee prosthesis ᎏ anteroposterior radiograph; Žb. Case 3: 13 months after revision to custom endo-rotating knee prosthesis ᎏ lateral radiograph.

J. Keenan et al. r The Knee 7 (2000) 165᎐170

Fig. 4. Case 5: Post-operative radiographs of primary PFC total knee replacement with femoral notching.

open reduction and internal fixation has been advocated by some authors, as this allows earlier mobilisation w6x and reduces malalignment, possibly improving the functional outcome compared with conservative techniques. Moran et al. w8x had no satisfactory results in nine displaced fractures treated non-operatively, and 10 satisfactory results in 15 displaced fractures treated with open reduction and internal fixation. However, internal fixation may be associated with a high incidence of complications Ž30᎐75%. and poor functional outcome w3,4,11x. Other authors report complication rates of only 10᎐19% w6,7x. Other fixation techniques have been reported, such as the use of a long stem Huckstep nail w13x, the

Fig. 5. Case 5: Radiographs of displaced supracondylar fracture above PFC total knee replacement.

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Fig. 6. Case 5: Post-operative radiographs of revision to custom endoprosthesis 4 weeks after periprosthetic fracture.

Brooker᎐Wills locking nail w14x, Rush pins w4,15x and Hoffman external fixation w3x. Figgie et al. w5x describe two cases of immediate revision using a custom prosthesis with distal femoral allograft. They noted that graft incorporation at the graft host junction had been slow to occur, but neither case had failed at the time of publication. Our experience demonstrates that the use of custom-made implants to treat low displaced supracondylar fractures above a TKA can give good implant alignment and fixation, whilst allowing a rapid recovery and mobilisation. This contrasts to techniques of internal fixation, which usually require a period of protected weight bearing and possibly bracing. Neither is well tolerated by overweight elderly patients, in whom these fractures usually occur. At present no long term follow-up is available, and relying on cemented stem fixation in osteoporotic bone is clearly worrying. The technique should probably be reserved for very low fractures in which fixation is technically challenging, or for failure of internal fixation. The flexibility of adjustment at the time of surgery enables a good technical result to be achieved with a resultant benefit in functional outcome. In the elderly, prosthetic replacement is probably preferable to allograft substitution, since it allows immediate full weight bearing. Rapid rehabilitation is of great importance to the patients, and the cost savings of earlier mobilisation and discharge serve to counter the high cost of the prosthesis.

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From our experience, we would not recommend the use of skeletal pin traction pre-operatively because of the risk of a subsequent deep-seated infection. References w1x Delport P, Van Audekerck R, Martens M, Muller J. Conservative treatment of ipsilateral supracondylar fracture after total knee arthroplasty. J Trauma 1982;24:864. w2x Webster D, Murray D. Complications of variable axis total knee arthroplasty. Clin Orthop 1985;193:160. w3x Merkel K, Johnson E. Supracondylar fracture of the femur after total knee arthroplasty. J Bone Jt Surg ŽA. 1986; 68A:29᎐43. w4x Nielson B, Peterson V, Varmarken J. Fracture of the femur after knee arthroplasty. Acta Orthop Scand 1988;59:155᎐157. w5x Figgie M, Goldberg V, Figgie H, Sobel M. The results of treatment of supracondylar fracture above total knee arthroplasty. J Arthrop 1990;5:267. w6x Culp R, Schmidt R, Hanks G, Mak A, Esterhai Jr. J, Heppenstall B. Supracondylar fracture of the femur following prosthetic knee replacement. Clin Orthop 1987;222:212᎐232. w7x Healy W, Siliski J, Incavo S. Operative treatment of distal femoral fractures proximal to total knee replacements. J Bone Jt Surg ŽA. 1993;75A:27᎐34.

w8x Moran M, Brick G, Sledge C, Dysart S, Chien E. Supracondylar femoral fracture following total knee arthroplasty. Clin Orthop 1996;324:196᎐209. w9x Mclaren A, Dupont J, Scoeber D. Open reduction internal fixation of supracondylar fractures above total knee arthroplasties using the intramedullary supracondylar nail. Clin Orthop 1994;302:194᎐198. w10x Cain P, Rubash H, Wissinger H, McClain E. Periprosthetic femoral fractures following total knee arthroplasty. Clin Orthop 1986;208:205᎐214. w11x Chen F, Mont M, Bachner R. Management of ipsilateral supracondylar femur fractures following total knee arthroplasty. J Arthrop 1994;9:521᎐526. w12x Neer C, Grantham S, Shelton M. Supracondylar fracture of the adult femur: a study of one hundred and ten cases. J Bone Jt Surg ŽA. 1967;49A:591᎐613. w13x Sekel R, Newman A. Supracondylar fractures above a total knee arthroplasty. A novel use of the Huckstep nail. J Arthrop 1994;9:445᎐447. w14x Hanks G, Mathews H, Routson G, Loughran T. Supracondylar fracture of the femur following total knee arthroplasty. J Arthrop 1989;4:289᎐292. w15x Ritter M, Stiver P. Supracondylar fracture in a patient with total knee arthroplasty. A case report. Clin Orthop 1985; 193:168᎐170.