Summary

We found an increased natural expression of the growth factors bFGF, BMP-12, VEGF, and TGF-b1 during tendon healing of rat Achilles tendons. External application of these growth factors improved the tendons failure load in the early healing phase.

Introduction

A review of the literature showed a discrepancy between biomechanical and clinical studies on fracture fixation failure in patients with poor bone quality.

The objective of the present study is to assess the influence of local bone status on complications after surgical treatment of proximal humerus fractures.

Introduction: Previous work has shown that fixation of meniscus tears supports healing by preventing tears from gapping. However, an anterior cruciate ligament (ACL) insufficiency might increase the loads especially on the posterior horns of the meniscus. The aim of this study was to test an ACL tear results in wider gaps of longitudinal meniscal tears.

Methods: 3 cm longitudinal tears were artificially set in the posterior horn of the medial menisci in 10 human cadaver knee joints. The medial plateau of the joints was replaced by a translucent copy, under which an arthroscope was positioned to observe the gapping phenomenon of the meniscal tears. The knee specimens were flexed and extended in a motion and loading simulator allowing for all degrees of freedom. The maximum gap width occurring during a flexion-extension cycle was registered.

Results: Longitudinal meniscal tears showed significantly wider gaps after cutting the ACL (p< 0.01). However, refixation of the tears with suture anchors significantly reduced the gap width to much lower values (p< 0.01), still higher then with intact ACL.

Conclusion: The results indicate that medial meniscal tears in the posterior horn are exposed to higher loads in case of an ACL insufficiency. A missing ACL leads to increased anterior instability, which obviously results in wider tear gaps also in case of tear fixation with an implant. This confirms from a biomechanical point of view the clinical finding that meniscus repair is significantly enhanced when combined with ACL reconstruction.

We examined 52 patients with acute Achilles tendon rupture (ATR), 43 men and 9 women, with a median age of 43 (28–68) years after percutaneous Achilles tendon repair with early functional therapy. 11 patients were treated in a cast (C) and 41 had a specially designed shoed (S). The mean follow-up was 56 (36–95) months. Patients suffering from health problems, which could affect their gait and balance (e.g. OA, spinal stenosis,…), as well as patients suffering from complications postoperatively, were excluded from the study. The mean Hannover Achilles Tendon Score was 81 (50 – 95) points (C = 81, S = 81).

Their calf muscle function studied three to eight years after treatment were found to have a significantly impaired dynamic muscle function of the calf muscles when tested in a specially constructed heel-raise test device. The Wilcoxon matched-pairs signed-ranks test showed a two-tailed P value of < 0,0001.

The average calf size was 38 (31–46,5) cm on the uninjured side and 36 (32–44,5) cm on the injured side. Only two patients had an equal calf size. Comparing the uninjured and injured side the two-tailed P value was found to be extremely significant < 0,0001.

The correlation between the maximum force and functional heel raise testing to the calf size on the injured side was weak with a Spearman correlation coefficient (r) = 0,33–38. There was no difference found between the patients treated in a cast and the patients treated in a shoe with percutaneous Achilles tendon repair and early functional therapy.

The principle finding in the present study was that the impact of an ATR is of great importance for the functional outcome than the treatment that is given. The difference in flexion strength and endurance between the injured and the uninjured side remained even after a 56 months follow-up. Therefore, calf size and functional muscle testing is a good tool to test functional outcome after Achilles tendon rupture. However, there was only a weak correlation between the size of atrophy and the amount of force reduction.

We have investigated whether control of balance is improved during stance and gait and sit-to-stand tasks after unilateral total hip replacement undertaken for osteoarthritis of the hip.

We examined 25 patients with a mean age of 67 years (sd 6.2) before and at four and 12 months after surgery and compared the findings with those of 50 healthy age-matched control subjects. For all tasks, balance was quantified using angular measurements of movement of the trunk.

Before surgery, control of balance during gait and sit-to-stand tasks was abnormal in patients with severe osteoarthritis of the hip, while balance during stance was similar to that of the healthy control group. After total hip replacement, there was a progressive improvement at four and 12 months for most gait and sit-to-stand tasks and in the time needed to complete them. By 12 months, the values approached those of the control group. However, trunk pitch (forwards-backwards) and roll (side-to-side) velocities were less stable (greater than the control) when walking over barriers as was roll for the sit-to-stand task, indicative of a residual deficit of balance.

Our data suggest that patients with symptomatic osteoarthritis of the hip have marked deficits of balance in gait tasks, which may explain the increased risk of falling which has been reported in some epidemiological studies. However, total hip replacement may help these patients to regain almost normal control of balance for some gait tasks, as we found in this study. Despite the improvement in most components of balance, however, the deficit in the control of trunk velocity during gait suggests that a cautious follow-up is required after total hip replacement regarding the risk of a fall, especially in the elderly.