Distal femoral varus osteotomy for valgus deformity of the knee

Distal femoral varus osteotomy for lateral compartment osteoarthritis in the valgus knee. A systematic review of the literature

The primary objectives of this systematic review were to define the indications, functional outcomes, survivorship and complications associated with distal femoral varus osteotomy (DFVO).Cumulative survival with arthroplasty as the endpoint ranged from 64 to 82% at 10 years, and 45% at 15 years. The mean pre-operative HSS score ranged from 46 to 65 and this improved at latest follow up to means of between 72 and 88. Pooled results show an overall complication rate of 5.8% (5/86) for unanticipated re-operation due to a complication.Poor reporting of included studies and considerable heterogeneity between them precluded any statistical analysis. Further study is required to determine the precise indications for DFVO, optimum surgical technique, implant of choice and post-operative rehabilitation regimen as all of these factors may significantly affect the complication profile and outcomes of this procedure.DFVO is technically demanding and requires a significant period of rehabilitation for the patient. However, long-term survivorship and good function have been demonstrated and it remains a potential option for valgus osteoarthritis in carefully selected patients.

Distal femoral dome varus osteotomy: surgical technique with minimal dissection and external fixation

The results obtained when employing distal femoral varus osteotomy are variable. Our objective was to describe a surgical technique involving minimal dissection, semicircular osteotomy with external fixation for valgus angular deformities, and early weight bearing.

DESIGN

Series of cases.

SETTING

Orthopedic Referral Trauma Center.

PATIENTS

Sixteen patients with valgus angular deformities of >12°.

INTERVENTION

Wedge varus osteotomy, minimal dissection with external fixation using a standard system, multidirectional Newfix. Main outcome measurements included pain, surgical time, knee flexion and extension angles, and assessment of knee function based on the Hospital Special Surgery knee rating scale (HSSkrs).

RESULTS

Of 16 patients, 14 were evaluated to the end of the study. When we compared preoperative values with those obtained postoperatively at a mean of 24±2.1months, pain measurement was reduced from 7 to 2.1 (p=0.002), angle of flexion was reduced from 105.4±14.6° to 105.3±11.1° (p=0.06), and angle of extension, from -1.67 to -1.25° (p=0.6), while HSSkrs assessment increased from 67.5±2.7 to 79.4±5 (p=0.003). Two patients were excluded from the study, one due to infection that developed along the trajectory of a screw, and the other patient underwent complete arthroplasty of the knee, which was performed to combat the pain that was not being alleviated.

CONCLUSIONS

The technique improves function and reduces pain while facilitating early rehabilitation in 83% of cases.

Distal femoral osteotomy: is internal fixation better than external?

BACKGROUND

Distal femoral osteotomies (DFO) can be used to correct deformities around the knee. Although osteotomies can be fixed with either internal or external fixation techniques, the advantages of one over the other are unclear.

QUESTIONS/PURPOSES

We asked whether (1) for both techniques, we could accurately correct the deformities based on our preoperative goals for mechanical axis deviation (MAD) and lateral distal femoral angle (LDFA), and (2) intraoperative times, (3) preoperative and postoperative knee ROM, and (4) complications differed.

PATIENTS AND METHODS

We identified 26 patients (34 limbs) who underwent femoral osteotomies. We compared accuracy of correction (based on correction of the MAD and the LDFA), duration of surgery, preoperative and postoperative knee ROM, and complications. The minimum followup was 20 months (mean, 29 months; range, 20-40 months).

RESULTS

We achieved the desired MAD within 10 mm of the goal in 18 of 21 limbs with the unilateral frame and in 12 of 13 limbs using fixator-assisted plating. Operative time for fixator-assisted plating was longer (122 ± 34 minutes) than when using a unilateral frame (94 ± 65 minutes). Preoperative and postoperative knee ROMs were similar for both techniques and there were no major complications.

CONCLUSIONS

We obtained accurate correction of deformities with both fixation techniques. Our experience suggests the method to be used should be left to the discretion of the surgeon and the needs and wishes of the patient after adequate explanation of the advantages and disadvantages.

LEVEL OF EVIDENCE

Level III, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.

Axial and torsional stability of supracondylar femur osteotomies: biomechanical comparison of the stability of five different plate and osteotomy configurations

PURPOSE

Little is known regarding the biomechanical stability and stiffness of implants and techniques used in supracondylar femur osteotomies (SCO). Therefore, fixation stability and stiffness of implants to bone was investigated under simulated physiological loading conditions using a composite femur model and a 3D motion-analysis system.

METHODS

Five osteotomy configurations were investigated: (1) oblique medial closing-wedge fixated with an angle-stable implant; (2) oblique and (3) perpendicular medial closing-wedge, both fixated with an angled blade plate; and lateral opening-wedge fixated with (4) a spacer plate and (5) an angle-stable lateral implant. The motion measured at the osteotomy was used to calculate the stiffness and stability of the constructs.

RESULTS

The least amount of motion and highest stiffness was measured in the medial oblique closing-wedge osteotomy fixated with the angled blade plate. The lateral opening-wedge techniques were less stable and had a lower stiffness compared with the medial; the oblique saw cuts were more stable and had a higher stiffness than the perpendicular.

CONCLUSION

This experimental study presents baseline data on the differences in the primary stability of bone-implant constructs used in SCO. The data in this study can be used as reference for future testing of SCO techniques. Furthermore, it is recommended that based on the differences found, the early postoperative rehabilitation protocol is tailored to the stability and stiffness of the fixation method used.

Distal femoral varus osteotomy outcome: Is associated femoropatellar osteoarthritis consequential?

INTRODUCTION

Distal femoral varus osteotomy (FVO) can be indicated for young active patients who have lateral unicompartmental osteoarthritis in a valgus knee originating in the femur. However, its indication remains controversial when associated patellofemoral osteoarthrosis is present.

HYPOTHESIS

Associated patellofemoral osteoarthrosis influences the results of osteotomy in cases of lateral tibiofemoral osteoarthrosis.

METHODS

Twenty patients (22 knees) underwent opening wedge FVO for lateral tibiofemoral osteoarthrosis of a valgus knee. The osteoarthrosis was lateral and unicompartmental in 11 cases, associated with patellofemoral osteoarthrosis in nine cases, and global in two cases. The osteotomy site was fixed with a 95° blade plate in all cases. At a mean follow-up of 54 months, all the patients were evaluated using the International Knee Society (IKS) score.

RESULTS

Eighteen knees had good or excellent results (80%), two had fair results (9.5%), and two had poor results (9.5%). One female patient underwent total knee replacement revision at 8 years and three others are awaiting total knee replacement. The mean preoperative IKS score increased from 49.28 (range, 14-70) to 74.23 (range, 41-92) at the last follow-up. The mean preoperative functional score increased from 50.68 (range, 30-80) to 72.85 (range, 40-90) at the last follow-up (p=0.001). The 8-year survival rate was 91% (confidence interval, 69-100%). We noted improvement in patellofemoral syndrome and recentering of the patella in seven cases out of nine with severe patellofemoral osteoarthrosis.

CONCLUSION

Distal femoral varus osteotomy, with lateral opening wedge and fixation can be a good alternative to treatment of lateral tibiofemoral osteoarthritis associated with a valgus knee originating in the femur. The association of patellofemoral osteoarthritis does not affect the functional results.

LEVEL OF EVIDENCE

Level IV. Retrospective study.

Closing wedge osteotomy of the tibia and the femur in the treatment of gonarthrosis

New developments in osteotomy techniques and methods of fixation have caused a renewed interest in closing wedge osteotomies of the tibia and femur in the treatment of gonarthrosis. The rationale, definition and techniques of closing wedge tibial and femoral osteotomies in the treatment of gonarthrosis are discussed. The principal indications include unicompartmental medial and much less so, varus knee gonarthrosis and unicompartmental lateral or valgus knee gonarthrosis with a well-maintained range of motion in patients who are physiologically young. Newer techniques have provided more rigid fixation and improved accuracy of correction.

Which osteotomy for a valgus knee?

A valgus knee is a disabling condition that can affect patients of all ages. Antivalgus osteotomy of the knee is the treatment of choice to correct the valgus, to eliminate pain in the young or middle age patient, and to avoid or delay a total knee replacement. A distal femoral lateral opening wedge procedure appears to be one of the choices for medium or large corrections and is particularly easy and precise if compared to the medial femoral closing wedge osteotomy. However, if the deformity is minimal, a tibial medial closing wedge osteotomy can be done with a faster healing and a short recovery time.

Distal femoral varus osteotomy for lateral osteoarthritis of the knee: a minimum ten-year follow-up

Distal femoral varus osteotomy (DFVO) may be indicated for symptomatic lateral compartment gonarthrosis associated with valgus deformity in younger, active patients. Thirty-three consecutive DFVOs (31 patients) with a minimum follow-up of ten years (mean 15.1, range 10-25) were reviewed. Fifteen DFVOs were converted to total knee arthroplasty (TKA) and one DFVO was awaiting TKA, reaching an overall failure rate of 48.5% at a mean of 15.6 years (range 6-21.5). Of the remaining 17 DFVOs, ten (58.8%) had good or excellent results, two (11.8%) had fair results and five (29.4%) had poor results. Mean modified Knee Society scores improved significantly (p < 0.01) from 36.8 preoperatively to 77.5 at one year post DFVO. DFVO is a viable treatment alternative for lateral compartment gonarthrosis. Conversion to TKA is expected to be required in approximately half of the patients at a mean of 15.6 years.

Varus distal femoral osteotomy in young adults with valgus knee

Background

Musculoskeletal disorders specially knee osteoarthritis are the most common causes of morbidity in old patients. Disturbance of the mechanical axis of the lower extremity is one of the most important causes in progression of knee osteoarthritis. The purpose of the present study was to analyze the surgical results of distal femoral varus osteotomy in patients with genu valgum.

Methods

In this study, after recording history and physical examination, appropriate radiographs were taken. We did varus distal femoral osteotomy by standard medial subvastus approach and 90-angle blade plate fixation then followed the patients clinically and radiographically.

Results

This study was done on 23 knees (16 patients) age 23.3 years (range, 17 to 41 years). The mean duration of following up was 16.3 months (range, 8 to 25 months). Based on paired T test, there were statistically significant difference between pre- and postoperative tibiofemoral and congruence angles (p < 0.001, t = 21.3 and p < 0.001, t = 10.1 respectively). Pearson correlation between the amount of tibiofemoral and congruence angle correction was also statistically significant (p = 0.02 and r = 0.46).

Conclusion

Distal femoral varus osteotomy with blade plate fixation can be a reliable procedure for the treatment of valgus knee deformity. In this procedure, with more tibiofemoral angle correction, more congruence angle correction can be achieved. Therefore, along with genu valgum correction, the patella should be stabilized simultaneously.

Femoral ledge sparing closing wedge osteotomy

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Lateral unicompartimental knee arthroplasty: indications, technique and short-medium term results

Lateral unicompartmental knee arthroplasty (UKA) is a valid alternative treatment in the event of arthritis confined to the lateral compartment. This paper examines its indications, technique and short to medium-term results. A total of 159 Miller-Galante cemented UKA prostheses (Zimmer, Warsaw, Indiana) were implanted consecutively (131 medial and 28 lateral) by the same surgeon. This study investigates 28 lateral UKAs in 27 patients. Twenty-five implants in 24 patients (including a subject operated bilaterally) were followed up for 12-60 months. Three patients were discarded on account of to short a follow-up period. The Hospital for Special Surgery (HSS) knee score was used to compare the pre- and post-operative results of the lateral UKA patients. The HSS score improved from a pre-op mean of 59.92 (range 48-68) to 88.04 (range 71-95) at the last follow-up. There was a positive increase in the pain, function and ROM components of the score. The lateral UKA prosthesis can be regarded as a sound alternative to total knee replacement. Correct patient selection on the basis of optimum surgical indications, however, is essential.

Long-term follow-up of distal femoral varus osteotomy of the knee

Distal femoral varus osteotomy (DFVO) of the knee may be indicated for young, active patients with unicompartmental arthritis and valgus deformity. We report on 40 DFVOs with a mean follow-up of 123 months. At the most recent follow-up, 24 knees had good or excellent results (60%), 3 had fair results (7.5%), and 3 had poor results (7.5%). Four in the fair/poor group were awaiting total knee arthroplasty. Eight knees (20%) had been converted to total knee arthroplasty. Mean Knee Society objective score improved from 18 (range, 0-74) to 87.2 (range, 50-100). Mean Knee Society function score improved from 54 (range, 0-100) to 85.6 (range, 40-100). Ten-year survival rate of the DFVO was 82% (95% confidence interval, 75%-89%) and the 15-year survival rate was 45% (95% confidence interval, 33%-57%).

Osteotomies: The Surgical Treatment of the Valgus Knee

Lateral compartment arthrosis from congenital valgus or the result of previous lateral meniscectomy can be a disabling condition. Realignment osteotomy, which may avoid or delay the need for a total knee replacement, is appropriate for young or middle-aged patients suffering from a painful valgus knee. Medium or large corrections can be managed with distal femoral lateral opening wedge osteotomy while minimal deformities are best treated with medial closing wedge tibial osteotomy.

Role of high tibial and distal femoral osteotomies in the treatment of lateral-posterolateral and medial instabilities of the knee

Mechanical alignment has been overlooked as an important contributor to knee stability with respect to collateral ligament laxity. The detrimental effects of varus or valgus limb malalignment become more obvious when the restraining force is lost because of ligamentous injury especially on the medial or the lateral/posterolateral side. Even with repair or reconstruction of these injuries, with repetitive load, the ligament will eventually fail to restore its structure and strength, resulting in failure and secondary restraint laxity. We have found that realignment of the limb is the most important factor in restoring a functional limb. After realignment, joint laxity, if persistent, can be addressed successfully with ligamentous reconstruction. Diagnosis and treatment of limb malalignment cannot be ignored in the management of chronic ligamentous instabilities, especially those with prior failed reconstruction. Our approach to these difficult problems and the preferred techniques of osteotomies on both tibial and femoral sides are described.

Distal femoral varus osteotomy for osteoarthritis of the knee. Surgical technique

BACKGROUND

Distal femoral varus osteotomy is a procedure that is performed for the treatment of lateralcompartment osteoarthritis of the knee as well as for correction of the associated valgus deformity. However, its role remains controversial and its efficacy in the treatment of associated patellofemoral arthritis has not been well studied. The purpose of the present study was to evaluate the outcome after distal femoral osteotomy performed for the treatment of painful genu valgum and to assess the influence of patellofemoral arthritis on the results.

METHODS

Thirty patients (thirty knees) were managed with distal femoral varus osteotomy for the treatment of noninflammatory lateralcompartment arthritis of the knee associated with a valgus deformity. Twelve knees had isolated lateral-compartment arthritis, ten had mild-to-moderate degenerative changes in the other two compartments, and eight knees had severe patellofemoral arthritis in addition to lateral-compartment disease. The osteotomy site was fixed with a 90 degrees blade-plate. After a mean duration of follow-up of ninety-nine months, all patients were evaluated with use of the Hospital for Special Surgery knee-rating system and a physical examination.

RESULTS

At the time of the most recent follow-up, twenty-five patients (83%) had a satisfactory result and two had a fair result according to the Hospital for Special Surgery rating system. The remaining three patients had had a conversion to a total knee arthroplasty. With conversion to total knee arthroplasty as the end point, the cumulative ten-year survival rate for all patients was 87% (95% confidence interval, 69% to 100%). Improvement in patellar tracking, which persisted at the time of the latest follow-up, was observed in seven of the eight knees with associated severe patellofemoral arthritis.

CONCLUSIONS

Distal femoral varus osteotomy with blade-plate fixation can be a reliable procedure for the treatment of lateral-compartment osteoarthritis of the knee associated with valgus deformity. The result of the osteotomy does not appear to be affected by the presence of severe patellofemoral arthritis.

Permanent patellar dislocation and osteoarthritis of the knee after femoral fracture in childhood. A case report

A 52 year-old woman suffered bilateral femoral shaft fractures when she was 5 years old and they were treated surgically. She had been able to walk without pain and giving way throughout her young and adult life, however, when she came to us with a 1-year history of the right knee pain, she could walk only 10 m continuously. The right knee revealed valgus deformity with complete lateral patellar dislocation. The femoro-tibial angle was 154 degrees and arthritic change was seen in the femorotibial joint. Surfaces of both the patella and the femur were degraded. Twenty-two degrees of rotational deformity was also found internally in the involved side. Varus osteotomy with external rotation of the distal fragment and lateral retinacular release combined with reefing of vastus medialis muscle were performed. Twenty-four months after surgery, knee score and functional score were, respectively, 85/100 and 71/100, using knee society clinical rating system and there was no pain associating patella incongruity.

Distal femoral varus osteotomy for osteoarthritis of the knee

BACKGROUND

Distal femoral varus osteotomy is a procedure that is performed for the treatment of lateral-compartment osteoarthritis of the knee as well as for correction of the associated valgus deformity. However, its role remains controversial and its efficacy in the treatment of associated patellofemoral arthritis has not been well studied. The purpose of the present study was to evaluate the outcome after distal femoral osteotomy performed for the treatment of painful genu valgum and to assess the influence of patellofemoral arthritis on the results.

METHODS

Thirty patients (thirty knees) were managed with distal femoral varus osteotomy for the treatment of noninflammatory lateral-compartment arthritis of the knee associated with a valgus deformity. Twelve knees had isolated lateral-compartment arthritis, ten had mild-to-moderate degenerative changes in the other two compartments, and eight knees had severe patellofemoral arthritis in addition to lateral-compartment disease. The osteotomy site was fixed with a 90 degrees blade-plate. After a mean duration of follow-up of ninety-nine months, all patients were evaluated with use of the Hospital for Special Surgery knee-rating system and a physical examination.

RESULTS

At the time of the most recent follow-up, twenty-five patients (83%) had a satisfactory result and two had a fair result according to the Hospital for Special Surgery rating system. The remaining three patients had had a conversion to a total knee arthroplasty. With conversion to total knee arthroplasty as the end point, the cumulative ten-year survival rate for all patients was 87% (95% confidence interval, 69% to 100%). Improvement in patellar tracking, which persisted at the time of the latest follow-up, was observed in seven of the eight knees with associated severe patellofemoral arthritis.

CONCLUSIONS

Distal femoral varus osteotomy with blade-plate fixation can be a reliable procedure for the treatment of lateral-compartment osteoarthritis of the knee associated with valgus deformity. The result of the osteotomy does not appear to be affected by the presence of severe patellofemoral arthritis.

Osteotomies around the Knee for the Young Athlete with Osteoarthritis

There exists a growing number of patients with osteoarthritis who are difficult to classify and treat due to their younger age and higher activity level. Many of these athletic patients have sustained meniscal injury, previous meniscectomy, or articular cartilage injury, and may develop osteoarthritic symptoms. Fewer patients present with underlying malalignment or ligamentous instability and increasing arthrosis. Ostoeomies about the knee have been shown to unload isolated medial and lateral compartment osteoarthritis and decrease symptoms in the older adult patient who has been considered too young for total knee replacement. We describe a treatment approach to the younger athlete with isolated unicompartmental osteoarthritis.

Inclination of the joint line in supracondylar osteotomy of the femur for valgus deformity

The inclination of the joint line after supracondylar osteotomy of the femur for valgus deformity was studied in 22 patients and 26 knees. The patients (four males and 18 females) were 17-77 years old (mean, 49.5 years). The obliquity of the joint line was measured in positive degrees (medial inclination) and negative degrees (lateral inclination). Mean obliquity was +3.1 degrees in the pre-operative study and -2.0 degrees in the post-operative study. A more horizontal joint line was obtained following surgical treatment (mean correction: 5.0 degrees ).

Bone realignment with use of temporary external fixation for distal femoral valgus and varus deformities

BACKGROUND

Correction of a distal femoral deformity may prevent or delay the onset of osteoarthritis or mitigate its effects. Accurate correction of deformity without production of a secondary deformity depends on precise localization and quantification of the deformity. We report a technique to correct distal femoral deformities in the coronal plane.

METHODS

Fourteen femora in thirteen skeletally mature patients with a distal femoral deformity underwent operative reconstruction. The preoperative deviation of the mechanical axis ranged from 90 mm laterally (genu valgus) to 120 mm medially (genu varus). The mechanical lateral distal femoral angle was abnormal in all fourteen knees. The technique consisted of application of an external fixator, performance of a percutaneous distal femoral dome osteotomy, correction of the deformity, and locking of the external fixator. A statically locked retrograde intramedullary nail was inserted following reaming, and the external fixator was removed. The mean duration of follow-up was thirty-three months (range, six to forty-seven months).

RESULTS

The mean time until healing was thirteen weeks (range, six to thirty-nine weeks). Nine of the thirteen patients reported an improvement in walking, and none needed an assistive device. All nine patients with preoperative knee pain were free of tibiofemoral pain at the most recent follow-up evaluation. The mechanical lateral distal femoral angle was within the normal range in twelve of the fourteen knees. The mechanical axis was within the normal range in ten lower extremities. In three of the four remaining limbs, the residual abnormal deviation of the mechanical axis was due to a residual tibial deformity.

CONCLUSIONS

Percutaneous dome osteotomy combined with temporary external fixation and insertion of an intramedullary nail can correct distal valgus and varus femoral deformities. We attributed the early mobilization of patients and the rapid bone-healing to the limited soft-tissue dissection, the low-energy corticotomy, and the use of intramedullary fixation in our surgical technique.

Cartilage resurfacing: filling defects

Chondral defects with no significant bone involvement can be managed arthroscopically using surface treatments such as debridement and drilling, abrasion arthroplasty, and microfracture. Chondral defects can also be managed arthroscopically using osteochondral autografts (mosaicplasty) or by cartilage cell transplant or periosteal grafts, both of which are performed in open surgery. The arthroscopic surface treatments are best reserved for small defects, but cell transplantation and mosaicplasty have been used for defects up to 3 cm in diameter. Periosteal grafting can be used for large defects affecting an entire condyle, but clinical experience with this procedure is limited and it is still considered investigational. Larger osteochondral defects (uncontained defects greater than 3 cm in diameter and greater than 1 cm in depth) are managed using osteochondral allografts. Realignment osteotomy should be considered in conjunction with any of these techniques in the presence of a coexisting deformity.

Common peroneal nerve palsy after lateral unicompartmental knee arthroplasty

Unicompartmental knee arthroplasty is now being used more commonly to treat single compartment disease of knee, with very encouraging results. We report on a rare case of common peroneal nerve palsy; 8 years after lateral unicompartmental knee arthroplasty. This palsy was caused by pressure on the common peroneal nerve, due to posterior migration of tibial component.

Double level osteotomy of the knee: a method to retain joint-line obliquity. Clinical results

BACKGROUND

Although general guidelines have been proposed for proximal tibial and supracondylar osteotomies, double level osteotomy provides the advantage of maintaining neutral joint-line obliquity in addition to correcting limb malalignment around the knee. The goal of this prospective study was to determine the outcome of double level osteotomy of the knee performed after analysis with computer-aided preoperative planning software in patients with varus malalignment.

METHODS

Twenty-nine double level osteotomies of the knee were performed in twenty-four patients. The patients were followed for an average duration of 82.7 months (range, twenty-seven to 137 months). All knees had moderate-to-severe varus deformity and arthritis. The mean preoperative mechanical tibiofemoral angle was 193.9 degrees (that is, 13.9 degrees of varus). Preoperative and postoperative evaluations included clinical (scores according to the Knee Society system), radiographic, and computer-aided analysis of the mechanical status of the knee joint. Failure was defined as conversion of an osteotomy to a total knee arthroplasty or the presence of severe pain in a patient who declined arthroplasty.

RESULTS

The mean clinical and functional scores according to the Knee Society system improved from 34 and 64 points, respectively, before the osteotomy to 90 (p < 0.0001) and 81 points (p = 0.079) at the time of the final follow-up examination. One patient was lost to follow-up. One of the twenty-nine knees was subsequently converted to total knee arthroplasty forty-nine months postoperatively. The cumulative rate of survival at 100 months was 96% (95% confidence interval, +4.5 to -8.7), with eight patients remaining at risk.

CONCLUSIONS

Double osteotomy is a valuable procedure for patients with such a large varus deformity that appropriate realignment and load transfer to the unaffected compartment, together with an acceptable joint-line obliquity, cannot be achieved by a single osteotomy.

Osteotomy of the knee: is there a seat at the table?

Osteotomy is an alternative treatment for unicompartmental osteoarthritis of the knee. In genu varum, a high valgus closing wedge osteotomy is preferred, with overcorrection by 5 degrees. Complications and poor outcomes can be overcome by incomplete osteotomy with careful preoperative planning, precise use of cutting jigs, compression fixation, and early mobilization and weight bearing. Patella baja is related to postoperative immobilization, and unicompartmental arthroplasties are more difficult to revise because of bone loss. Supracondylar femoral osteotomy is preferred for genu valgum using a lateral opening wedge with a toothed plate, allowing easy access to the lateral compartment of the knee. Osteotomy, far from being obsolete, has an increasing role in joint resurfacing procedures.

Alterations in the patella after a high tibial or distal femoral osteotomy

Knee osteotomies realign the knee in an attempt to better distribute forces across the knee. The anatomic and physiologic function of the extensor mechanism, which includes the quadriceps tendon, patella, and patella ligament, may be altered during this procedure. An understanding of these changes is important especially when additional surgery becomes necessary, such as a conversion to a total knee arthroplasty. The current authors discuss patella mechanics and changes in the patella associated with osteotomies about the knee and the influence on normal patella biomechanics. Although patella changes are uncommon after a distal femoral osteotomy, poor total knee arthroplasty outcomes after a high tibial osteotomy attributable to patella alterations exist. Surgical technique during the primary high tibial osteotomy and the conversion to the total knee arthroplasty can reliably improve the final outcome. Rigid internal fixation with early knee mobilization after high tibial osteotomy reduces the incidence of patella baja and improves total knee arthroplasty outcome after a high tibial osteotomy, whereas while patella changes after a distal femoral osteotomy are minimal and largely ignored.

Supracondylar osteotomy of the femur with use of compression. Osteosynthesis with a malleable implant

BACKGROUND

The goal of treatment of a valgus deformity of the knee that is secondary to osteoarthritis of the lateral compartment is to obtain axial correction of the malalignment of the extremity. Osteosynthesis of the osteotomized femur with use of internal fixation and a stiff implant has not been as successful as expected. We evaluated the accuracy and maintenance of correction and the stability of fixation with a malleable plate after a supracondylar osteotomy of the distal aspect of the femur that was performed to correct a valgus deformity of the knee.

METHODS

We performed an incomplete oblique osteotomy of the distal aspect of the femur in nineteen patients (twenty-one knees) and stabilized the osteotomy site with a malleable semitubular plate, which was bent to form an angled plate, and lag-screws. Postoperatively, the patients were immediately encouraged to walk, with partial weight-bearing on the affected extremity. The mean age of the patients was fifty-seven years (range, thirty-nine to seventy-one years), and the mean duration of follow-up was five years (range, two to twelve years).

RESULTS

In seventeen knees, the osteosynthesis withstood the mechanical loading that occurred during the postoperative functional rehabilitation program. Prolonged use of crutches or immobilization, or both, was necessary after the operation in three knees. The osteosynthesis failed in one knee. The loss of correction in eighteen knees, after bone-healing, averaged 1.7 degrees (range, 0 to 4 degrees).

CONCLUSIONS

Our method of achieving osteosynthesis is based on the concept that inherent endogenous stability mechanisms can be mobilized by circumferentially compressing the two cortical tubes with the cut ends congruently apposed to each other. We believe that our technique provides an alternative to osteosynthesis with use of a stiff implant such as a fixed-angle blade-plate device.

Degenerative arthritis of the knee in active patients: evaluation and management

The natural history and treatment of degenerative arthritis of the knee in active patients is a topic of great interest, with continually evolving concepts and techniques. Osteoarthritis is a spectrum of clinical entities, ranging from focal chondral defects to established arthrosis resulting from biologic and biomechanical hyaline cartilage failure. Evaluation of the active patient with knee arthritis should include a comprehensive history emphasizing symptom manifestation, activity level, and previous surgical treatment. The physical examination must include an evaluation of extremity alignment, gait patterns, and coexisting disorders of the spine and adjacent joints. Diagnostic testing is usually straightforward and should include the 45-degree flexion weight-bearing posteroanterior plain radiograph. Nonsurgical treatment modalities include rehabilitation, lifestyle modification, bracing, supportive devices, and medical management, including use of the new chondroprotective oral and injectable agents. Several surgical options exist, each with specific indications. Arthroscopic debridement can provide a positive, but often short-lived, reduction in the severity of symptoms. Tibial or femoral osteotomy may maintain the patient's active lifestyle and delay the need for arthroplasty. Unicompartmental and total knee arthroplasty can each provide reliable relief of symptoms but may not permit a return to the activities that the patient values.

Distal femoral osteotomy for lateral compartment osteoarthritis of the knee

Twenty-one patients with lateral compartment osteoarthritis and valgus deformity of the knee underwent distal femoral supracondylar osteotomy (medial closing wedge) between 1983 and 1993 with follow-up ranging from 1 to 8 years. Ten knees had plaster cast immobilization, 5 had fixation with 2 staples supplemented with a plaster cast, and 6 knees had rigid internal fixation with an AO blade plate. Thirty-three percent of patients had a satisfactory result using the HSS score, and 57% had a satisfactory result using the Knee Society Clinical Rating. Fifty-seven percent had a significant complication, including severe knee stiffness requiring manipulation under anesthesia (48%), nonunion/delayed union (19%), infection (10%), and fixation failure (5%). Five (19%) knees required total knee replacement within 5 years of surgery. Satisfactory results were obtained only in those patients who had less severe degrees of osteoarthritis confined to the lateral compartment (grades I to III), adequate correction of valgus deformity (the anatomical axis within 2 degrees from zero), and rigid internal fixation to permit postoperative early mobilization. These results indicate that distal femoral osteotomy is a satisfactory procedure in the young, active patient with osteoarthritis of the lateral compartment of the knee, but requires precise surgical technique and rigid internal fixation.

Articular cartilage repair

Articular cartilage can tolerate a tremendous amount of intensive and repetitive physical stress. However, it manifests a striking inability to heal even the most minor injury. Both the remarkable functional characteristics and the healing limitations reflect the intricacies of its structure and biology. Cartilage is composed of chondrocytes embedded within an extracellular matrix of collagens, proteoglycans, and noncollagenous proteins. Together, these substances maintain the proper amount of water within the matrix, which confers its unique mechanical properties. The structure and composition of articular cartilage varies three-dimensionally, according to its distance from the surface and in relation to the distance from the cells. The stringent structural and biological requirements imply that any tissue capable of successful repair or replacement of damaged articular cartilage should be similarly constituted. The response of cartilage to injury differs from that of other tissues because of its avascularity, the immobility of chondrocytes, and the limited ability of mature chondrocytes to proliferate and alter their synthetic patterns. Therapeutic efforts have focused on bringing in new cells capable of chondrogenesis, and facilitating access to the vascular system. This review presents the basic science background and clinical experience with many of these methods and information on synthetic implants and biological adhesives. Although there are many exciting avenues of study that warrant enthusiasm, many questions remain. These issues need to be addressed by careful basic science investigations and both short- and long-term clinical trials using controlled, prospective, randomized study design.

Current concepts in the treatment of articular cartilage defects

Over time, articular cartilage loses the capacity to regenerate itself, making repair of articular surfaces difficult. Lavage and debridement may offer temporary relief of pain for up to 4.5 years, but offer no prospect of long-term cure. Likewise, marrow-stimulation techniques such as drilling, microfracture, or abrasion arthroplasty fail to yield long-term solutions because they typically promote the development of fibrocartilage. Fibrocartilage lacks the durability and many of the mechanical properties of the hyaline cartilage that normally covers articular surfaces. Repair tissue resembling hyaline cartilage can be induced to fill in articular defects by using perichondrial and periosteal grafts. However, these techniques are limited by the amount of tissue available for grafting and the tendency toward ossification of the repair tissue. Autogenous osteochondral arthroscopically implanted grafts (mosaicplasty), or open implantation of lateral patellar facet (Outerbridge technique), requires violation of subchondral bone. Osteochondral allografts risk viral transmission of disease and low chondrocyte viability, in addition to removal of host bone for implantation. Autologous chondrocyte implantation offers the opportunity to achieve biologic repair, enabling the surgeon to repair the joint surface with autologous articular cartilage. With this technique, care must be taken to ensure the safety, viability, and microbial integrity of the autologous cells while they are expanded in culture over a 4- to 5-week period prior to implantation. Surgical implantation requires equal attention to meticulous technique. In the future, physiologic repair also may become possible using mesenchymal stem cells or chondrocytes delivered surgically in an ex vivo-derived matrix. This would allow in vitro manipulation of cells with growth factors, mechanical stimuli, and matrix sizing to allow implantation of mature biosynthetic grafts which would allow treatment of larger defects with decreased rehabilitation and morbidity.

Total knee replacement in young, active patients. Long-term follow-up and functional outcome

We reviewed our experience with total knee arthroplasties performed between 1977 and 1992 in patients who were fifty-five years old or less to determine the appropriate management for younger patients who have severe osteoarthrosis. One hundred and fourteen knee replacements were performed in eighty-eight patients who were an average of fifty-one years old (range, twenty-two to fifty-five years old). All of the operations were performed by one of the two senior ones of us (J. N. I. or W. N. S.) with the use of cementing techniques. A posterior stabilized, posterior cruciate-substituting design was used for all but one replacement, for which a semiconstrained total condylar prosthesis was used. Six knees (four patients) were lost to follow-up. Follow-up data for the remaining 108 knees (eighty-four patients) were used to perform the survivorship analysis. One hundred and three unrevised knees (eighty patients) were available for clinical evaluation with the scoring systems of The Hospital for Special Surgery and the Knee Society at an average of eight years (range, three to eighteen years) postoperatively; thirty-six knees were followed for more than ten years. In addition, the activity levels of the patients were assessed with the activity score of Tegner and Lysholm. Radiographs were examined for evidence of loosening of the component. At the latest follow-up examination, the average knee score according to the system of The Hospital for Special Surgery had improved from 55 points preoperatively to 92 points. According to the system of the Knee Society, the average knee score was 94 points and the average functional score was 89 points. The result for all 103 knees was good or excellent according to the knee scores of The Hospital for Special Surgery and the Knee Society. Ninety-seven knees (94 per cent) had good or excellent function according to the functional score of the Knee Society. The average activity score of Tegner and, Lysholm improved from 1.3 points (range, 0 to 4 points) preoperatively to 3.5 points (range, 1 to 6 points) at the latest follow-up examination. All but two patients had improvement in the activity score postoperatively, and nineteen (24 per cent) of the eighty patients had an activity score of at least 5 points, indicating regular participation in activities such as tennis, skiing, bicycling, or strenuous farm or construction work. Nine (9 per cent) of the 103 knees had non-progressive tibial radiolucent lines. Two patients had a revision because of late infection, and one patient had revision of a well fixed tibial component because of wear of the polyethylene. In addition, three patellar components were revised for loosening, and one spacer was exchanged to treat instability. With failure defined as revision of either the femoral or the tibial component, the over-all rate of survival was 94 per cent at eighteen years. When the three patellar revisions were included in the failures, the survival rate was 90 per cent at eighteen years. When the exchange of the spacer was also included in the failures, the survival rate was 87 per cent at eighteen years. We consider arthroplasty with cementing of a posterior stabilized total knee prosthesis to be effective operative treatment with durable results for osteoarthrosis in younger patients when other, less invasive measures have failed. Within the average eight-year follow-up interval of this study, polyethylene wear, osteolysis, and loosening of the conforming posterior cruciate-substituting prosthesis were not major problems for these younger, active patients, although it is possible that this observation could change with an even longer duration of follow-up.

Varus osteotomy of the distal part of the femur. A survivorship analysis

Varus osteotomy of the distal part of the femur is often the procedure of choice for the treatment of osteoarthrosis of the lateral compartment associated with genu valgum. We followed twenty-one knees (twenty patients) long term or until failure. At the most recent evaluation (average, 133 months; range, ninety-seven to 240 months), thirteen osteotomies were still successful, seven had failed, and one patient (in whom the knee had remained functional) had died. Of the seven failures, three occurred early (at twelve or twenty-four months) and four occurred late (between seventy-two and ninety-eight months). The probability of survival at ten years was 64 per cent (95 per cent confidence interval, 48 to 80 per cent), as determined with use of the Kaplan-Meier method. We concluded that, with proper selection of patients, this procedure is effective for the treatment of gonarthrosis of the lateral compartment associated with valgus deformity.

Posterolateral arthritis of the knee

Arthritis in the posterolateral quadrant of the knee presents typical arthroscopic findings. With careful history, physical examination, and appropriate radiographs, it can be an office diagnosis. The history, physical findings, and arthroscopic findings in 15 patients with this problem were reviewed. Symptoms of posterolateral pain, give-way, and pain with stairclimbing were common. The only frequent physical findings were those of pain with the lateral meniscal entrapment test or pain with the pivot shift test. No ligamentous instability was noted. Weight-bearing radiographs demonstrated severe lateral chondral loss in flexion, but not in extension. Arthroscopic findings were typical. Previous injury to the posterior portion of the lateral meniscus was common. This seems to be a traumatic, rather than a degenerative, process. Three patients had varus-producing osteotomy of the distal femur. This was not effective in relieving their symptoms.

Symptomatic Valgus Knee: The Surgical Options

Valgus knee deformities requiring surgery are difficult to manage due to the relative rarity and abnormal biomechanics of the condition and the unique soft-tissue and osseous pathologic features. Surgical options include arthroscopic debridement, abrasion arthroplasty, proximal tibial varus osteotomy, distal femoral varus osteotomy, combined femoral-tibial varus osteotomy, unicompartmental knee arthroplasty, and total knee arthroplasty. Each procedure has its own indications, contraindications, and limitations.

Distal femoral osteotomy for valgus deformity of the knee

Distal femoral varus osteotomy and blade-plate fixation for valgus deformity of the knee proved effective in restoring axial alignment in 18 of 36 knees (34 patients). Patients were followed for an average of 5.4 years (range: 2 to 19 years). The osteotomies were performed on 14 men and 22 women (average age: 44 years; range: 14 to 77). The patients' average preoperative valgus deformity of the anatomical axis was 19.4 degrees (range: 8 degrees to 33 degrees). The surgical procedures performed were a medial closing wedge osteotomy (14 knees) and a lateral opening wedge osteotomy with bone grafting (22 knees). Postoperative correction of the anatomical axis averaged 3.8 degrees valgus (range: 8 degrees varus to 20 degrees valgus). Maximum improvement was reached within 6.3 months by patients who were less than 60 years old and within 5.1 months by patients who were more than 60 years old. Pain decreased or resolved in 21 of 35 knees (60%); activity level improved in 24 of 35 knees (69%). One patient was unavailable for follow up evaluation. Varus osteotomy in the distal femur was concluded to be an acceptable form of treatment in the valgus knee alone or associated with traumatic or osteoarthritis of the lateral compartment.