Osteochondritis dissecans of the knee

A case of osteochondritis dissecans of the knee is described in which the site of the lesion, on the supero-medial aspect of the lateral femoral condyle, is unique. This case supports the theory that direct recurrent minor trauma causes osteochondral fractures which remain ununited producing the characteristic lesion.     

Osteochondritis dissecans of the knee

Osteochondritis dissecans is a condition of the joints that appears to affect subchondral bone primarily, with secondary effects on articular cartilage. With progression, this pathology may present clinically with symptoms related to the integrity of the articular cartilage. Early signs, associated with intact cartilage, may be related to a softening phenomenon and alteration in the mechanical properties of cartilage. Later stages, because of the lack of underlying support of the cartilage, can present with signs of articular cartilage separation, cartilage flaps, loose bodies, inflammatory synovitis, persistent or intermittent joint effusion, and, in severe cases, secondary joint degeneration. Selecting and recommending a surgical intervention require balancing application of nonsurgical interventions with assessment of the degree of articular cartilage stability and the potential for spontaneous recovery.     

Osteochondritis dissecans of the knee joint

Osteochondritis dissecans is a disorder with a prevalence of 0.01 to 0.06 %. Men between 16 and 36 years of age are most commonly affected by it. In the western hemisphere, the knee is affected by this progressive disorder in 75 % of the cases, specifically the medial femoral condyle (70 - 80 %). The etiology is uncertain, although genetic defects, micro-trauma, ossification disorders and ischemia have been implicated. Pathogenetically, Osteochondritis dissecans is classified in four stages, whereas in stage one, there is merely a subchondrial edema. Without therapy this could lead to stage 4, with a free osteochondral joint fragment. Treatment is analogous with the stage of the disorder. Whereas conservative treatment may yield full recovery during stage 1, starting in stage 2, invasive treatment should be considered. When the cartilage surface remains intact retrograde procedures are indicated. If the cartilage is injured anterograde therapies, like the chondral or osteochondral transplantation, should be used.     

Tibial condylar fractures fixed with totally absorbable, self-reinforced polyglycolide screws

Six patients with displaced split-depression-type tibial condylar fractures were treated with absorbable, self-reinforced polyglycolide screws. One patient underwent reoperation because of an unacceptable primary fracture reduction unrelated to the implant material. The others healed well, with good functional and anatomical results despite one slight redisplacement in a medial condylar fracture treated without plaster cast immobilisation. Absorbable polyglycolide screws seem to be suitable for the fixation of selected tibial condylar fractures. The implant removal operation is thus avoided.     

Osteochondritis dissecans of the knee. A long-term study.

Twenty-two knees with osteochondritis dissecans diagnosed before skeletal maturity were followed prospectively into middle age: 32% had radiographic evidence of moderate or severe osteoarthritis at an average follow-up of 33.6 years; only half had a good or excellent functional result. We found that osteoarthritis was more likely to occur if the defect was large or affected the lateral femoral condyle.     

Osteochondritis dissecans of the knee: arthroscopic compression screw fixation

This article describes repair of osteochondritis dissecans of the knee by arthroscopic compression screw fixation and reports the healing response and clinical result. Diagnostic and operative arthroscopy was performed. Compression screw fixation was used. The exact operative technique varied depending on the status of the lesion. The patients were non-weight bearing for 2 months, after which a second surgery was necessary for removal of the metallic screw(s). The initial healing response was assessed by the firmness of the lesion to palpation at the second look. Subsequent x-ray evidence of healing was correlated with the clinical outcome. Ninety-four percent of the knees were determined to be initially healed at the time of the second look. Four of these apparently solid repairs subsequently loosened and required repeat surgery. Eighty-eight percent of the patients assessed their results as excellent or good after 2 years minimum follow-up. Arthroscopic compression screw fixation is an effective method of repair for mild to moderately severe cases of osteochondritis dissecans.     

Fixation of horizontal maxillary osteotomies with biodegradable self-reinforced absorbable polylactide plates: preliminary results

Totally biodegradable, self-reinforced polylactide plates and titanium miniscrews were used for the fixation of horizontal maxillary osteotomies in 32 patients. In two cases the fixation was unstable because of technical problems. In the others the analysis of cephalometric radiographs between immediate and late postoperative showed very similar figures, indicating postoperative stability. There were no complications in the healing due to this biodegradable osteofixation in these patients.     

Intraosseous cellular response to biodegradable fracture fixation screws made of polyglycolide or polylactide

Summary As biodegradable pins and screws have increasingly been used in the internal fixation of fractures, sterile inflammatory reactions have occasionally occurred. The aim of the present experimental study was to assess the cellular response within cancellous bone to biodegradable polyester screws. In 45 rabbis a transverse distal femoral osteotomy was fixed with a 4.5 × 30 mm screw made either of polyglycolide (PGA, in 20 rabbits) or polylactide (PLA, in 25 rabbits). The follow-up times were 3, 6, 12, 36 or 48 weeks. The time-related and spatial characteristics of the cellular response were examined histomorphometrically using standardised sample fields under polarised-light microscopy. Polymorphonuclear granulocytes and mononuclear round cells were scarce in all follow-up groups. The occurrence of phagocytic cells (mononuclear macrophages and foreign-body giant cells) was highest in the PGA-fixed 12-week specimens. The giant cells seemed to adhere to the implant surface at an early stage, whereas the ultimate digestion and clearing of the decomposing polymeric material later on were performed by macrophages invading the implant body. No PGA was left in the 36-week specimens, while the gross geometry of the PLA screws was still intact at 48 weeks. In conclusion, the inflammatory response to these polymers was quite mild. Thus it seems probable that some other additional factors must influence the occurrence of the clinical inflammatory reactions.     

Osteochondritis dissecans of the lateral femoral condyle of the knee joint.

Differences in the features of osteochondritis dissecans (OCD) affecting the lateral and medial femoral condyles were investigated in 13 patients (14 knees) treated from 1991 to 1994. OCD affected the lateral femoral condyle in 6 knees (lateral group) and the medial condyle in 8 knees (medial group). The lateral group was younger (mean age, 14 v. 20 years). The radiological stage (Brückl) of the lateral group was stage 2 in 3 knees and stage 3 in 3. The lateral menisci were all discoid and the condylar articular surface of the lesions was normal in two knees, softened in 3 and detached in 1. The medial group comprised 1 knee in stage 2, 1 in stage 3, 1 in stage 4, and 5 in stage 5. The OCD lesion showed softening in 2 knees and detachment in 6. Repetitive abnormal stress on weaker osteochondral structures in the growing period produced by a discoid meniscus during growth may cause OCD of the lateral femoral condyle.     

Osteochondritis dissecans of the lunate

Osteochondritis dissecans of the lunate appears to be extremely rare. A case is reported with no predisposing abnormality and with no history of previous trauma. The problem was successfully managed by arthroscopic surgery.