There have been conflicting reports on the effects of gamma irradiation on the material properties of cortical allograft bone. To investigate changes which result from the method of preparation, test samples must be produced with similar mechanical properties to minimise variations other than those resulting from treatment.

We describe a new method for the comparative measurement of bone strength using standard bone samples. We used 233 samples from six cadavers to study the effects of irradiation at a standard dose (28 kGy) alone and combined with deep freezing. We also investigated the effects of varying the dose from 6.8 to 60 kGy (n = 132).

None of the treatments had any effect on the elastic behaviour of the samples, but there was a reduction in strength to 64% of control values (p < 0.01) after irradiation with 28 kGy. There was also a dose-dependent reduction in strength and in the ability of the samples to absorb work before failure

We suggest that irradiation may cause an alteration in the bone matrix of allograft bone, but provided it is used in situations in which loading is within its elastic region, then failure should not occur.

Aims

Conventional patient-reported surveys, used for patients undergoing total hip arthroplasty (THA), are limited by subjectivity and recall bias. Objective functional evaluation, such as gait analysis, to delineate a patient’s functional capacity and customize surgical interventions, may address these shortcomings. This systematic review endeavours to investigate the application of objective functional assessments in appraising individuals undergoing THA.

Aims

Internal hemipelvectomy without reconstruction of the pelvis is a viable treatment for pelvic sarcoma; however, the time it takes to return to excellent function is quite variable. Some patients require greater time and rehabilitation than others. To determine if psoas muscle recovery is associated with changes in ambulatory function, we retrospectively evaluated psoas muscle size and limb-length discrepancy (LLD) before and after treatment and their correlation with objective functional outcomes.

Aims

Type 2 diabetes mellitus (T2DM) impairs bone strength and is a significant risk factor for hip fracture, yet currently there is no reliable tool to assess this risk. Most risk stratification methods rely on bone mineral density, which is not impaired by diabetes, rendering current tests ineffective. CT-based finite element analysis (CTFEA) calculates the mechanical response of bone to load and uses the yield strain, which is reduced in T2DM patients, to measure bone strength. The purpose of this feasibility study was to examine whether CTFEA could be used to assess the hip fracture risk for T2DM patients.

Hand function was evaluated in 105 patients who had been operated on in early infancy for brachial plexus birth palsy. The mean follow-up after surgery was for 13.4 years (5.0 to 31.5). Fine sensation, stereognosis, grip and pinch strength and the Raimondi scale were recorded.

Fine sensation was normal in 34 of 49 patients (69%) with C5–6 injury, 15 of 31 (48%) with C5–7 and in 8 of 25 (32%) with total injury. Loss of protective sensation or absent sensation was noted in some palmar areas of the hand in 12 of 105 patients (11%). Normal stereognosis was recorded in 88 of the 105 patients (84%), whereas only 9 of the 105 (9%) had normal grip strength. The mean Raimondi scale scores were 4.57 (3 to 5) (C5–6), 4.26 (1 to 5) (C5–7) and 2.16 (0 to 5) in patients with total injury.

The location of impaired sensation was related to the distribution of the root injury. Avulsion type of injury correlated with poor recovery of hand function.

The outcome of surgery in patients with medial epicondylitis of the elbow is less favourable in those with co-existent symptoms from the ulnar nerve. We wanted to know whether we could successfully treat such patients by using musculofascial lengthening of the flexor-pronator origin with simultaneous deep transposition of the ulnar nerve. We retrospectively reviewed 19 patients who were treated in this way. Seven had grade I and 12 had grade IIa ulnar neuropathy. At a mean follow-up of 38 months (24 to 48), the mean visual analogue scale pain scores improved from 3.7 to 0.3 at rest, from 6.6 to 2.1 with activities of daily living, and from 7.9 to 2.3 at work or sports, and the mean disabilities of the arm, shoulder and hand scores improved from 42.2 to 23.5.

These results suggest that this technique can be effective in treating patients with medial epicondylitis and coexistent ulnar nerve symptoms.

The ability to predict load-bearing capacity during the consolidation phase in distraction osteogenesis by non-invasive means would represent a significant advance in the management of patients undergoing such treatment. Measurements of stiffness have been suggested as a promising tool for this purpose. Although the multidimensional characteristics of bone loading in compression, bending and torsion are apparent, most previous experiments have analysed only the relationship between maximum load-bearing capacity and a single type of stiffness. We have studied how compressive, bending and torsional stiffness are related to the torsional load-bearing capacity of healing callus using a common set of samples of bone regenerate from 26 sheep treated by tibial distraction osteogenesis.

Our findings showed that measurements of torsional, bending and compressive stiffness were all suitable as predictors of the load-bearing capacity of healing callus. Measurements of torsional stiffness performed slightly better than those of compressive and bending stiffness.