The Knee
The outcome of 23 Oxford unicondylar knee replacements revised to total knee replacements was assessed with an average follow up of 4.1 years. At revision, 30% of the cases had required reconstruction for bone deficiency. Bone graft, when needed, was obtained from the revision cuts. One patient required re-revision for recurrent sepsis. The remainder included 10 excellent, 3 good, 2 fair and 2...
To determine which axes on the short radiograph (36 cm 43 cm) correlate best with the corresponding axes on the long radiograph (36 cm 130 cm), 100 long anteroposterior radiographs were taken postoperatively following total knee arthroplasty. The central 43 cm of the long radiograph were used to simulate a short radiograph of the knee. For the femur, the short-radiograph axis drawn...
This paper describes the use of continuous passive motion (CPM) in 14 knees with stiffness after total knee replacement. CPM resulted in a significant increase in flexion and also reduction of flexion deformities. This increase occurred in both rheumatoid and osteoarthritic patients. The mean increase during CPM treatment was 26°. There was a mean loss of 10° with a minimum follow up of 6 months...
Data on artificial knee implantation in the USA were obtained from the Medical Device Implant Supplement to the 1988 National Health Interview Survey, a nationally representative, population-based survey of 47 485 households and 122 310 individuals. The survey identified 214 knee implant recipients with 263 implants. Projected to the 1988 non-institutionalized USA adult population, these represent...
The anteroposterior tibial translations caused by simulated isometric quadriceps forces of up to 750 N were measured in vitro for two extension-restraining load placements at five flexion angles. Both quadriceps force and tibial translation were flexion-angle and load-placement dependent. Quadriceps force was linearly dependent on restraining force; tibial displacement was either very small (<1...
The results of cementless meniscal bearing total knee replacements are presented with an average follow up of 94 (range 78-112) months. Patients who were younger and in good health were selected for this uncemented knee prosthesis: 29 low contact stress total knee replacements were performed in 27 consecutive patients of whom four patients died from unrelated causes. We reviewed 25 knees in 23 patients...
We interviewed 231 consecutive patients with osteoarthritis undergoing knee replacement surgery and examined them for evidence of risk factors and bilateral disease. Bilateral knee replacement surgery was performed on 17% of patients; 50% of patients had a knee replacement with no radiographic evidence of osteoarthritis in the unoperated knee. There was an increased ratio of women to men undergoing...
Whether to retain or sacrifice the posterior cruciate ligament during total knee replacement is controversial. This review examines the evidence for and against retention of the ligament and suggests circumstances in which the ligament should be sacrificed and those in which it is advantageous to keep it. The review discusses the function and anatomy of the posterior cruciate ligament, a historical...
A universal blade cooler for bone cutting in total knee replacement is described.
The purpose of the study was to identify mechanoreceptors in the lateral collateral ligament of the human knee. Ten ligaments from ten fresh cadavers were studied by light microscopy. In addition to free nerve endings, two types of mechanoreceptors were identified. They were located at the femoral and fibular attachments and on the surface of the ligament. These findings support the theory that...
We report three cases of pigmented villonodular synovitis (PVNS), which presented with a locked knee in the absence of significant trauma. After clinical examination all patients were strongly suspected to have a mechanical derangement of the knee. Two patients underwent arthroscopic resection of the mass which on histology proved to be PVNS, one patient needed a small arthrotomy to remove the PVNS...
Bone-patellar tendon grafts, consisting of the central one-third of the patellar tendon and a small flake of bone from the tibial crest, were harvested bilaterally from six adult female goats. Animals were killed 13 or 52 weeks after surgery. Mediolateral and craniocaudal radiographs of the operated stifle joints demonstrated two distinct patterns of bone response around the graft harvest site....
The loads on high density polyethylene components, and hence the likelihood of wear, may be reduced in knee replacement by conforming high contact area surface geometry. Unless in combination with a mobile ( meniscal ) component, however, the relative lack of torsional resilience with such geometry is itself a further potential cause for overload and wear. We report a case with severe wear believed...
The Kneelax arthrometer is a tibia referenced system for objectively testing and reproducing the anterior stability of the anterior cruciate ligament (ACL). It measures the extent of anterior translation of the tibia on the femur, under anterior drawer forces of 44, 67, 89, and 132 N. The compliance of the system, calculated as the increase in anterior displacement between the 67 and 89 N level,...
This case report describes a patient with recurrent traumatic superior dislocation of the patella treated by arthroscopic removal of the interlocking osteophytes.
We present a prospective review of 30 partial anterior cruciate ligament ruptures. After arthroscopic diagnosis we evaluated the tear and made a clear definition of partial tear. Detailed evaluation was correlated with the functional outcome of treatment.
Allograft bone was used in eight patients to reconstruct tibial and femoral bone deficiencies in revision total knee arthroplasty of previously septic knees. At a mean of 30.1 months after revision, none had recurrence of sepsis. One patient required resection arthroplasty three weeks postoperatively because of skin flap necrosis. These results suggest that allografts of bone are useful in reconstructing...
Using a knee motion analyser, we have studied anterior tibial translation under a range of loading conditions in normal and anterior cruciate ligament (ACL) deficient knees. Anterior displacement in excess of that observed in passive knee flexion was noted in a static Lachman test. Anterior tibial displacement in normal knees increased steadily as the knee was extended from 60° flexion reaching a...
We performed a randomized doubled-blind study to evaluate whether there was a benefit in delay in tourniquet deflation with intra-articular administration of morphine and bupivacaine following operative arthroscopic surgery. In 34 patients the tourniquet was deflated immediately and in 38 patients the tourniquet remained inflated for 10 min following injection. The analgesic efficacy was assessed...
We report a case of traumatic horizontal intra-articular dislocation of the patella. This rare injury is usually seen in adolescent males and typically requires open reduction. Our patient was an 88-year-old woman who was treated by manipulation under general anaesthetic with a good result.