Background-After Achilles tendon repair, immediate weightbearing and immobilisation closer to neutral plantarflexion are thought to limit atrophy and stiVness, but may place deleterious stress on the repair. Objectives-To estimate the relative stress on the Achilles tendon during weightbearing with immobilisation in varying degrees of plantarflexion. Conclusions-When the ankle is immobilised, stress on the Achilles tendon is determined by the degree of plantarflexion and the contractile activity of the plantarflexors. In the immobilised ankle, the addition of a 1 inch heel lift was suYcient to minimise plantarflexor activity during walking. (Br J Sports Med 2001;35:329-334) Keywords: Achilles tendon; EMG; heel lifts; soleus; gastrocnemius Although there is still some debate about open versus closed management of Achilles tendon disruption, 1 2 most authors agree that surgical repair is the treatment of choice. Until recently, surgical repair followed by cast immobilisation in plantarflexion and non-weightbearing for six weeks was considered the ideal treatment. However, new controversy has arisen from recent studies that show that early mobilisation seems to enhance the healing of the repair. Methods-Electromyographic3-9 Many authors are now advocating early range of motion (ROM) based on animal 10-14 and hand studies 15 that show increased healing rates and strength while preventing the side eVects of prolonged joint immobilisation, such as joint stiVness, muscular atrophy, cartilage atrophy, deep vein thrombosis, tendocutaneous adhesions, skin necrosis, and disuse osteoporosis.2 8 16 17 If the tendon experiences tension during healing, orientation of collagen fibres and strength of the calf muscles are improved, as are tendon vascularity, 11-13 18 breaking strength, and number of collagen filaments. 19 With early ROM and weightbearing protocols, patients are obtaining power and strength that is almost equal to that of the opposite good leg.3 5 6 8 By contrast, repair followed by six weeks of cast immobilisation results in appreciable residual weakness. 1 20-22 Early ROM and progressive weightbearing appear to result in few failures or complications.5 23-25 However, there is limited clinical research available on which to base the timing and progression of rehabilitation after Achilles tendon repair. For example, cam-walkers are commonly used to provide protected weightbearing by immobilising the ankle in varying degrees of plantarflexion. However, the degree of protection aVorded to the Achilles tendon with the use of such immobilisers is not known.When the ankle is immobilised, stress on the Achilles tendon during gait is determined by the degree of plantarflexion and the contractile activity of the plantarflexors. The degree of plantarflexion can be controlled by using a ROM adjustable cam-walker. Alternatively, cam-walkers with the axis fixed at 90°can be used, and increased plantarflexion can be achieved by inserting heel lifts into the camwalker. The magnitude of contractile activity during...

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Fifty patients whose surgical approach violated the arterial geniculate circulation to the patella were evaluated to determine the subsequent effect on patella viability. Comparative postoperative radionuclide scans in 100 knees, 50 control and 50 surgical, revealed an avascular insult in only 7 knees (14%). It appears that the intratendinous circulation described by Björkström and Goldie protects the patella from an avascular insult in the presence of geniculate arterial disruption.

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Background Guidelines support aspirin thromboprophylaxis for primary total hip and knee arthroplasty (THA and TKA) but supporting evidence has come from high volume centers and the practice remains controversial. Methods We studied 4562 Medicare patients who underwent elective primary THA (1736, 38.1%) or TKA (2826, 61.9%) at 9 diverse hospitals. Thirty-day claims data were combined with data from the health system’s electronic medical records to compare rates of venous thromboembolism (VTE) between patients who received prophylaxis with: (1) aspirin alone (47.3%), (2) a single, potent anticoagulant (29%), (3) antiplatelet agents other than aspirin or multiple anticoagulants (21.5%), or (4) low-dose subcutaneous unfractionated heparin or no anticoagulation (2.2%). Sub-analyses separately evaluating THA, TKA and cases from lower volume hospitals (n = 975) were performed. Results The 30-day VTE incidence was 0.6% (29/4562). VTE rates were equal in patients receiving aspirin and those receiving a single potent anticoagulant (0.5% in both groups). Patients with VTE were significantly older than patients without VTE (mean 76.5 vs. 73.1 years, P = 0.04). VTE rate did not associate with sex or hospital case volume. On bivariate analysis considering age, aspirin did not associate with greater VTE risk compared to a single potent anticoagulant (OR = 2.1, CI = 0.7–6.3) with the numbers available. Odds of VTE were increased with use of subcutaneous heparin or no anticoagulant (OR = 6.4, CI = 1.2–35.6) and with multiple anticoagulants (OR = 3.6, CI = 1.1–11.2). THA and TKA demonstrated similar rates of VTE (0.5% vs. 0.7%, respectively, P = 0.43). Of 975 cases done at lower volume hospitals, 387 received aspirin, none of whom developed VTE. Conclusions This study provides further support for aspirin as an effective form of pharmacological VTE prophylaxis after total joint arthroplasty in the setting of a multi-modal regimen using 30-day outcomes. VTE occurred in 0.7% of primary joint arthroplasties. Aspirin prophylaxis did not associate with greater VTE risk compared to potent anticoagulants in the total population or at lower volume hospitals.