Large osteochondral defects of the femoral condyle: press-fit transplantation of the posterior femoral condyle (MEGA-OATS)

BACKGROUND AND AIMS: Large osteochondral defects in the weight-bearing zone of the knee remain a challenging therapeutic problem. Surgical options include drilling, microfracturing, and transplantation of osteochondral plugs but are often insufficient for the treatment of large defects of the femoral condyle. PATIENTS AND METHODS: Large osteochondral defects of the femoral condyle (mean defect size 7.2 cm(2) range 3-20) were treated by transplantation of the autologous posterior femoral condyle. Between 1984 and 2000, 29 patients were operated on: in 22 the medial, in 6 the lateral femoral condyle, and in one the trochlear groove was grafted. Thirteen patients underwent simultaneous high tibial valgus osteotomy. In the first series (1984-1999) the graft was temporarily fixed with a screw ( n=12), but from 1999 we used a newly developed press-fit technique ( n=17) avoiding screw fixation of the graft. The operative technique comprising graft harvest, defect preparation, transplantation, and fixation is described. Patients were clinically evaluated using the Lysholm score, and magnetic resonance imaging with intravenous contrast was performed 6 and 12 weeks after surgery (mean follow-up 17.7 months (range 3-46). RESULTS: Pain and swelling were reduced in 26 patients. Three patients of the first series reported persistent problems and were subjectively not satisfied. The mean Lysholm score rose from preoperatively 52 to 77 points after 3 months, 74 after 6, 88 after 12, and 95 after 18. Magnetic resonance imaging showed good graft viability in all cases. We saw one arthrofibrosis after 6 months but noted no problems related to the loss of the missing posterior condyle. CONCLUSION: Large osteochondral defects of the femoral condyle can be treated by transplantation of the autologous posterior femoral condyle. The use of only one osteochondral piece renders better approximation of the femoral cartilage curvature and thus joint congruence than in mosaic plasty. However, whether loss of the posterior condyle has a long-term negative impact on the knee joint remains to be elucidated.     

MRI of osteochondral defects of the lateral femoral condyle: incidence and pattern of injury after transient lateral dislocation of the patella

OBJECTIVE: The typical bone bruise pattern involving the anterolateral femoral condyle and inferomedial patella after transient lateral dislocation of the patella is a well-described MRI finding. In our study, however, we sought to determine the incidence and location of lateral femoral condyle osteochondral injuries after transient lateral dislocation of the patella. CONCLUSION: Osteochondral defects of the lateral femoral condyle are a common sequela after transient lateral patellar dislocation. A significant number of osteochondral injuries involve the midlateral weight-bearing portion of the lateral femoral condyle and are more posterior than would be expected after transient dislocation of the patella.     

An anatomic-arthrographic study of the relationships of the lateral meniscus and the popliteus tendon.

The anatomy of the posterior lateral knee joint is studied through photography and radiography of plastic corrosion casts of the knee joint. The images thus obtained are compared to in vivo arthrograms. This anatomic-arthrographic correlation clearly demonstrates how the bursal extensions of the joint space about the popliteus tendon dictate the location and arthrographic appearance of the peripheral attachments of the posterior lateral meniscus. The casts also serve to illustrate a discussion of anatomic variation, embryology, and function of the popliteus apparatus. The largely unappreciated direct action of the popliteus muscle on the lateral meniscus is emphasized.     

Patellar tendon–lateral femoral condyle friction syndrome: MR imaging in 42 patients

OBJECTIVE: To demonstrate the MR imaging findings that occur between the posterior inferolateral patellar tendon and the lateral femoral condyle in patients with chronic anterior and or lateral knee pain. PATIENTS AND DESIGN: A retrospective review of the MR images in 42 patients who presented with chronic anterior or lateral knee pain was performed by two musculoskeletal radiologists. In 15 patients, post-contrast images were available. RESULTS: Sagittal and axial imaging planes best demonstrated the patellar tendon and its relationship with the lateral femoral condyle. In 40 patients, there was obliteration of the fat planes and abnormal signal intensity in the lateral soft tissues of the inferior patellofemoral joint. Enhancement after administration of gadolinium was noted in all cases in which contrast was administered. Eighteen patients showed cystic changes in the soft tissues adjacent to the lateral femoral condyle in addition to fat plane obliteration. In two patients, only cystic changes were noted in the lateral soft tissues. Abnormal patellar alignment was noted in 37 patients. Patellar tendon pathology was seen in nine patients. CONCLUSION: In evaluating anterior knee symptoms, MR imaging allows identification of changes that may be related to patellar tendon-lateral femoral condyle friction syndrome and that should be distinguished from other causes of anterior or lateral knee pain.     

Bilateral osteochondritis dissecans of lateral femoral condyle

A 20-year-old male with bilateral osteochondritis dissecans (OD) of the distal lateral femoral condyle is presented. OD can occur in many joints; however, the medial femoral condyle of the knee is the most common. Bilateral OD of the distal lateral femoral condyle is extremely rare. In our case, the lesion on the right side was traumatic and the lesion on the left side was self-induced. We performed open surgery for both knees. The fragments were stabilized with multiple Herbert screws. This case supports the theory that a defect in the ossification center of the distal lateral femoral condyle plays a role in the etiology of osteochondritis dissecans.     

Displaced osteochondral fracture of the lateral femoral condyle associated with an acute anterior cruciate ligament avulsion fracture: a corollary of "the lateral femoral notch sign"

Anterior cruciate ligament (ACL) rupture is usually accompanied by bone contusions resulting from impact of tibia on femur. The injury sometimes becomes manifest as a depression on the lateral femoral condyle giving rise to "lateral femoral notch" sign. The authors describe a rare case of impaction of the tibia and femur resulting in an osteochondral fracture rather than the usual bone contusion, which frequently occurs with ACL rupture. Open reduction and internal fixation of both the ACL avulsion fracture and the osteochondral fracture from the lateral femoral condyle were done, and the patient had a good outcome at 1-year follow-up. Level of evidence V.     

Fresh osteochondral allografting in the treatment of osteochondritis dissecans of the femoral condyle

BACKGROUND: The treatment of osteochondritis dissecans in the adult knee can be challenging. As part of our comprehensive treatment program, fresh osteochondral allografts have been used in the surgical management of osteochondritis dissecans of the femoral condyle. HYPOTHESIS: Fresh osteochondral allograft transplantation will provide a successful surgical treatment for osteochondritis dissecans of the femoral condyle. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Sixty-six knees in 64 patients underwent fresh osteochondral allografting for the treatment of osteochondritis dissecans. Each patient was evaluated both preoperatively and postoperatively using an 18-point modified D'Aubigné and Postel scale. Subjective assessment was performed using a patient questionnaire. Radiographs were evaluated preoperatively and postoperatively. RESULTS: Mean follow-up was 7.7 years (range, 2-22 years). There were 45 men and 19 women with a mean age of 28.6 years (range, 15-54 years). All patients had undergone previous surgery. Forty-one lesions involved the medial femoral condyle, and 25 involved the lateral femoral condyle. All were osteochondritis dissecans type 3 or 4. The mean allograft size was 7.5 cm(2). One knee was lost to follow-up. Of the remaining 65 knees, 47 (72%) were rated good/excellent, 7 (11%) were rated fair, and 1 (2%) was rated poor. Ten patients (15%) underwent reoperation. The mean clinical score improved from 13.0 preoperatively to 16.4 postoperatively (P < .01). Fifty-nine of 64 patients completed questionnaires. Subjective knee function improved from a mean of 3.4 to 8.4 on a 10-point scale (P < .01). CONCLUSION: With greater than 70% good or excellent results, fresh osteochondral allograft transplantation is a successful surgical treatment for osteochondritis dissecans of the femoral condyle.     

Osteoarthritis of the patella, lateral femoral condyle and posterior medial femoral condyle correlate with range of motion

Purpose

The type of osteoarthritis and the degree of severity which causes restriction of knee range of motion (ROM) is still largely unknown. The objective of this study was to analyse the location and the degree of cartilage degeneration that affect knee range of motion and the connection, if any, between femorotibial angle (FTA) and knee ROM restriction.

Methods

Four hundreds and fifty-six knees in 230 subjects with knee osteoarthritis undergoing knee arthroplasty were included. Articular surface was divided into eight sections, and cartilage degeneration was evaluated macroscopically during the operation. Cartilage degeneration was classified into four grades based on the degree of exposure of subchondral bone. A Pearson correlation was conducted between FTA and knee flexion angle to determine whether high a degree of FTA caused knee flexion restriction. A logistic regression analysis was also conducted to detect the locations and levels of cartilage degeneration causing knee flexion restriction.

Results

No correlation was found between FTA and flexion angle (r = ?0.08). Flexion angle was not restricted with increasing FTA. Logistic regression analysis showed significant correlation between restricted knee ROM and levels of knee cartilage degeneration in the patella (odds ratio (OR) = 1.77; P = 0.01), the lateral femoral condyle (OR = 1.62; P = 0.03) and the posterior medial femoral condyle (OR = 1.80; P = 0.03).

Conclusion

For clinical relevance, soft tissue release and osteophyte resection around the patella, lateral femoral condyle and posterior medial femoral condyle might be indicated to obtain a higher degree of knee flexion angle.

Level of evidence

Case–control study, Level III.     

Isolated avulsion of the popliteus tendon. A case report

We have reported a rare case of an isolated avulsion of the popliteus tendon. In this case the avulsed tendon was associated with a large osteochondral fragment that was easily relocated and fixed anatomically. We believe that the popliteus tendon is important to the mechanics of the knee. We would recommend the treatment as presented in this case should one of these rare cases be encountered.     

Subchondral impaction fractures of the non-weight-bearing portion of the lateral femoral condyle

Objective

To document the first report of intra-articular, non-weight-bearing, impaction fractures of the lateral femoral condyle.

Materials & methods

Institutional Review Board and Regional Ethics Committee approval for this study was obtained and patient informed consent deemed unnecessary. We prospectively documented all potential cases of non-weight-bearing posterior subchondral impaction fractures of the femoral condyles diagnosed on magnetic resonance imaging (MRI) of the knee performed at our institution between January 2006 and December 2011. The cases were reviewed and discussed by three experienced musculoskeletal radiologists and only cases satisfying pre-defined MRI criteria were included.

Results

Sixteen cases of intra-articular impaction fractures in a posterior, non-weight-bearing area of the lateral femoral condyle were diagnosed in patients with a mean age of 40. Eight were associated with recreational sports activities and 4 with repeated kneeling. There were no fractures documented in the non-weight-bearing aspect of the medial femoral condyles. Proposed underlying mechanisms for development of this type of fracture are presented.

Conclusion

Awareness, along with a high level of suspicion, that non-specific knee pain, especially in patients involved in athletic activities, could be due to intra-articular impaction fractures of the non-weight-bearing posterior aspect of the lateral femoral condyle is essential and MRI is the mainstay of diagnosis.     

A ganglion of the patellar tendon in patellar tendon-lateral femoral condyle friction syndrome

Intratendinous ganglia are rare. We report the case of a sedentary woman with chronic mechanical anterolateral pain of the knee and an extensive ganglion of the patellar tendon as indicated on magnetic resonance (MR) and ultrasound (US) examinations. There was evidence of a high-riding patella, patellar malalignment and patellar tendon-lateral femoral condyle friction syndrome with significantly close contact between the patellar tendon and the lateral facet of the femoral trochlea. The ultrasound-guided aspiration of the ganglion enabled a localized injection of an anti-inflammatory drug (cortivazol) and the cytopathological examination of the fluid, which confirmed the diagnosis. Clinical improvement was maintained with knee rehabilitation and was satisfactory at follow-up after 1 year. To our knowledge, we report the first case of a ganglion of the patellar tendon subsequent to patellar tendon-lateral femoral condyle friction syndrome. We found that this case was illustrative of mucoid degeneration in connective tissue due to chronic repetitive microtraumas. Additionally, this case provided the opportunity to discuss the management of this condition in a sedentary individual with a high-riding patella and patellar malalignment.     

Prospective evaluation of prolonged fresh osteochondral allograft transplantation of the femoral condyle: minimum 2-year follow-up

BACKGROUND: Focal articular cartilage lesions of the knee in young patients present a therapeutic challenge. Little information is available pertaining to the results after implantation of prolonged fresh grafts. HYPOTHESIS: Prolonged fresh osteochondral allografts present a viable option for treating large full-thickness articular cartilage lesions. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: This study presents the results of 25 consecutive patients who underwent prolonged fresh osteochondral allograft transplantation for defects in the femoral condyle. The average patient age was 35 years (range, 17-49 years). The average length of follow-up was 35 months (range, 24-67 months). Prospective data were collected using several subjective scoring systems, as well as objective and radiographic assessments. RESULTS: Statistically significant improvements (P < .05) were seen for the Lysholm (39 to 67), International Knee Documentation Committee scores (29 to 58), all 5 components of the Knee injury and Osteoarthritis Outcome Score (Pain, 43 to 73; Other Disease-Specific Symptoms, 46 to 64; Activities of Daily Living Function, 56 to 83; Sport and Recreation Function, 18 to 46; Knee-Related Quality of Life, 22 to 50), and the Short Form-12 physical component score (36 to 40). Overall, patients reported 84% (range, 25% to 100%) satisfaction with their results and believed that the knee functioned at 79% (range, 35% to 100%) of their unaffected knee. Radiographically, 22 of the grafts (88%) were incorporated into host bone. CONCLUSION: Fresh osteochondral allograft transplantation is an acceptable intermediate procedure for treatment of localized osteochondral defects of the femur. At 2-year follow-up, it is well incorporated and offered consistent improvements in pain and function. CLINICAL RELEVANCE: Prolonged fresh allograft transplantation is a safe and effective technique for addressing symptomatic osteoarticular lesions in the knees of young patients.     

Cartilage thickness matching of selected donor and recipient sites for osteochondral autografting of the medial femoral condyle

Osteochondral transplantation requires a careful assessment of the location of donor plugs. A mismatch of cartilage thickness between the donor and recipient site may lead to abnormal stresses and poor function. The objective of this study was to characterize the recommanded donor and recipient sites with respect to cartilage thickness in younger individuals. Nineteen arthro CT (13 men, 6 women), which had been carried out in a population of less than 50 years old were studied. Recommanded donor sites have included the posterior femoral condyles, the medial and lateral aspect of the trochlea and central, medial and lateral sides of the intercondylar notch. Recipient sites were studied at four regions of interest on the medial femoral condyle usually involved in osteochondritis dissecans. Average cartilage thickness was calculated on the digital version of the reference cuts for each site and compared. The sensitivity of the precision of the measurements to observer variability was evaluated using intra- and inter-observer correlation coefficient tests. The femoral cartilage in the knee was thickest in the recipient sites (2.49 mm, SD 0.64) than in donor sites (1.79 mm, SD 0.43) (P < 0.0001). There was no differences between the different donor sites, unless for the antero lateral intercondylar notch which was significantly thinner (1.3 mm, SD 0.29) than the other sites (P < 0.05). The cartilage of the donor site was consistently thinner than the cartilage of the recipient sites. Between the different donor sites, the lateral side of the intercondylar notch was significantly thinner than the other donor sites and should not be harvested in priority.     

Mucoid degeneration of the anterior cruciate ligament with erosion of the lateral femoral condyle

We report a case of a mucoid degeneration of the anterior cruciate ligament (ACL) that produced osseous erosion of the medial aspect of the lateral femoral condyle. The MRI findings and differential diagnosis are discussed.     

Parathyroid carcinoma. Report of three cases.

Primary or relapsing hyperparathyroidism should not be considered a result only of benign conditions like adenoma or hyperplasia (primary or secondary). Parathyroid carcinoma is often the real cause but, because of its rarity, sometimes it is either overlooked or misdiagnosed. Even histologic classification can be erroneous. Distant metastases or ectopic location of the tumors are another potential cause of misdiagnosis, especially when management is decided without the help of diagnostic imaging modalities, particularly those related to the functional aspect of the tumors or their metastases, such as the Tl-201/Tc-99m subtraction scan and the Tl-201 whole body scan.     

Spontaneous osteonecrosis of the knee involving both the medial femoral condyle and the medial tibial plateau: report of three cases

Spontaneous osteonecrosis of the knee (SPONK) usually involves a single condyle or plateau. The medial femoral condyle (MFC) is most often involved and spontaneous osteonecrosis of the medial tibial plateau (MTP) is a rare condition, representing only 2% of all necroses reported in the knee. SPONK involving both the MFC and the MTP is extremely rare. SPONK occurring in either the MFC or the MTP individually might extend to the corresponding side of the knee in the advanced end-stage; however, in that situation, significant degenerative changes would exist and it might be difficult to differentiate end-stage SPONK form severe osteoarthritis. SPONK affecting both the MFC and the MTP without significant secondary osteoarthritic changes has not been reported, even though it is difficult to know which occurs first. We have cared for three patients with histologically proven osteonecrosis of the MFC and MTP and report their radiologic features.     

The use of a single osteochondral autograft plug in the treatment of a large osteochondral lesion in the femoral condyle: an experimental study in sheep

BACKGROUND: The use of osteochondral autograft plugs can be restricted because of limited amount of donor material. HYPOTHESIS: A small osteochondral autograft plug placed in the center of a large defect in a sheep femoral condyle will yield results superior to either an untreated or a bone-grafted defect. STUDY DESIGN: Controlled laboratory study. METHODS: Twelve adult sheep underwent bilateral hindlimb surgery. On 1 limb, a 6-mm circular osteochondral autograft plug was placed in the center of a 10-mm circular defect in the medial femoral condyle. The gap between the plug and the condyle was filled with bone graft. On the contralateral side, the defect was either left untreated or filled with bone graft (control specimens). Animals were studied at 6 and 12 months under gross examination, high-resolution radiography, and histologic evaluation. RESULTS: At 6 months, 4 of 6 plugs healed and showed good maintenance of the joint surface and cartilage viability in the plugs. One plug fractured and resorbed, and 1 plug settled but healed. At 1 year, all 5 plugs healed, 1 having settled slightly (1 animal died earlier). The plug specimens showed better maintenance of the condyle contour at both times, and the central plug had hyaline-appearing cartilage. The control specimens were more irregular, had a fibrocartilage fill, and appeared flatter, although no gross cavitation or collapse was indicated. Composite cartilage scores on histologic evaluation were significantly higher for the plug specimens after 6 months (P = .02) and 1 year (P = .036) compared with controls. CONCLUSION: At 6 months and 1 year, a 6-mm osteochondral plug placed in a 10-mm defect better preserved the articular surface and contour of the condyle compared to untreated or bone-grafted defects. CLINICAL RELEVANCE: Osteochondral autograft plugs may be able to treat larger articular lesions without complete fill of the defect.