Introduction: Various techniques have been described for cup position in deficient acetabuli. Medialization allows an optimal cup position in the true acetabulum affording cover of the implant in the superolateral area by the bony roof and avoiding the need for a structural graft to cover the protruding lateral edge of the cup.

Materials and Methods: During the last 5 years 51 cases of cup medialization have been done during Resurfacing Replacement or THR with hard-hard bearing surfaces (mean follow up 35.2 month). 15 cases were done with the medial acetabuloplasty technique and 36 cases were done by simple over-reaming the medial wall and morselized bone grafting. The mean followed up was 16 months.

Surgical technique: Medial Acetabuloplasty: After a cartilage removal, we drill perforations in a horizontal line to weaken the central area of the medial wall. Using an impactor the medial wall is fractured and shifted medially for a few millimeters and the cavitation so produced is filled with morselized bone graft. This technique preserves a shell of bone medially which together with the graft brings about medial bony wall preservation. In extreme acetabular deficiency, this technique is also useful by minimizing the extent of morselized bone grafting needed in the superolateral area for lateral roof bone formation.

Results: The medial wall defect was consistently reformed during the first year. In neither the over-reaming with morselized bone graft nor in the group using the medial acetabuloplasty was the stability of the cup compromised.

Conclusion: The lateral structural graft techniques are more cumbersome, take more time and the results are less certain.

In the short term there was no difference in hip scores or in the radiological assessment between medialization with or without acetabuloplasty. We suggest this technique seems to have the potential for very good long term results.

Introduction: Extracorporal Shock Wave Therapy (ESWT) has become a useful adjunct for the treatment of various musculo-skeletal inflammatory conditions.

The aim of the study is prospective assessment of the efficacy of ESWT for the treatment of recalcitrant greater trochanteric bursitis (GTB).

Material and Methods: Prospective evaluation and follow-up of fourteen patients with persistent GTB two of them with bilateral problem. All the patients failed to response to conventional treatment with oral NSAID’s, physiotherapy, US and more than one steroid injection to the grater trochanter region. All patients underwent compete physical examination. A Comprehensive VAS Score (grading from 0–10) which were obtained prior to therapy and at follow-up. ESWT was applied in six consequitive courses each of 1500 impulses of 0.32mj/mm^2 to the lateral side of the grater trochanter region.

Results: Mean age of 60.6 ± 11.6 (mean ± SD) years (range 81 to 38 years). Mean duration of symptoms 14.2 ± 8.1 months, up to 37 months. Mean VAS dropped from 7.9 ± 0.9 to 1.6 ± 0.8 (p< 0.0001). There were no side effects except minimal local discomfort during the session time.

Conclusion: ESWT is an effective treatment for recalcitrant GTB, with minimal side effect.

Introduction: In avascular necrosis [AVN] of the femoral head the dead bone undergoes osteoclastic osteolysis and is replaced by newly synthesized, immature, weak bone, which cannot withstand the daily loads. The articular surface might caves in because of these changes, and osteoarthritic joint changes can develop. Alendronate interferes with the osteoclastic activities, it can slow-down the bone turnover of the necrotic bone and can differ these changes.

The aim of this study is to delay the speedy renewal of living epiphyses by alendronate medication in order to describe the effects of it on the fate of the necrotic femoral heads in rats.

Methods: Sixty female sprague-dawley rats, 6-month old weighing about 400–500 grams, underwent surgical AVN of the right femoral heads. Forty-four rats, the treated group, were treated with alendronate 200 μgm/kg/day. Sixteen rats, the control group, were treated with saline. Both groups were daily injected subcutaneously for six weeks and sacrificed. Both femoral heads were harvested and were evaluated microscopically and stained by H& E.

Results: The necrotic femoral heads of the control group, which were not treated by alendronate, were severely distorted with osteoarthrosis features as; collapse of the epiphysis, pannus formation, filling of spaces by chronically and mildly inflamed densely textured fibrous tissue which was polluted by numerous tiny particles of necrotic bone. Additionally, large chunks of necrotic articular cartilage were haphazardly scattered in the fibrous tissue. All hematopoietic and fat cells of the intertrabecular spaces of the epiphysis were replaced by fibrous tissue. More often than not, the cartilage of the physis was focally or entirely absent such that osseous trabeculae of the epiphysis and metaphysis linked with each other, forming so-called epiphyseal-metaphyseal bridges. The above described alterations were encountered in all animals, yet their severity varied.

The decisive difference between the necrotic femoral heads of otherwise untreated in opposition to the alendronate-medicated rats was the preservation of a hemispherical configuration of the femoral heads. There was no distortion of the femoral heads in the alendronate-treated animals and the femoral heads preserved their roundness.

All femoral heads of the non-operated left hips were microscopically normal.

Discussion: It has become clear that the degree of architectural distortion of the femoral epiphyses depends on the extent of bone turnover leading to resorption of all debris and its replacement by living osseous and soft tissues. The more rapidly and more extensively the reconstruction of living epiphyses progresses, the smaller is the prospect of reshaping a hemispherical or near-hemispherical femoral head. The recently rebuilt epiphyses cannot carry daily transarticular loads without caving in. The revascularization-related reconstitution of weak bony trabeculae is blamed for the collapse of the femoral heads. If this indeed is the case, the remodeling of the necrotic femoral heads should be delayed, rather than sped-up. Alendronate interferes with the osteoclastic activities and hence, slowing-down the bone turnover.

The osteoclastic activity is detrimental for the conservation of a hemispherical femoral head because of the rapidly occurring replacement of the necrotic bone by living tissues. Halting the activities of the osteoclasts by a biphosphonate would stop the hasty osteoneogenesis, which is responsible for the early femoral capital disfigurement and might delay the regeneration of osteo-arthiritic changes of the joint later on.

Introduction: The aim of the current investigation to study the inherent ability of biomaterial scaffolds to regenerate bone defects without osteoinductive growth factors. We have developed a biosynthetic hybrid scaffold that mimics the biofunctionality of the provisional fibrin matrix which regulated the initial stages of in vivo bone regeneration. The material is comprised of a fibrinogen backbone and polyethylene glycol (PEG) cross-links that regulate the strength, durability, and degradation of the matrix during the healing process. Precise control over the degradability of the hydrogel scaffold provides the ability to systematically regulate the cellular infiltration associated with fracture healing. Furthermore, improved physical strength (over purified native fibrin clots) enables superior handling properties and stable in situ fixation.

Materials & Methods: In the current study, a 7-mm critical size defect is created in the right tibia of female Sprague-Dawley rats (age 3–4 months); an external fixator is placed proximal and distal to the mid-section of the tibia. Pre-cast fibrinogen-PEG cylindrical hydro-gels (3-mm dia, 7-mm long) are placed into the site of the defect. Three different hydrogel compositions are tested: 1:1, 1:2, and 1:3 fibrinogen to PEG. Independent experiments demonstrate that higher concentrations of PEG give the hydrogels slower degradation kinetics. Radiographs, post operative and during follow-up, and histological evaluation were done.

Results & Discussion: Both radiography and histological evaluation reveals extensive and widespread periosteal new bone formation. Post-operative radiographs show the formation of a periosteal callus in the gap region of treated animals after five weeks compared to immediately following excision (Figure 1, right). Five weeks post-operatively, histological sections stained with H& E reveal a thick covering of newly formed and moderately differentiated lamellar-fibred bone alongside lengthy stretches of the original cortex. There are large amounts of closely packed trabeculae of recently deposited, woven-fibered bone wherever there are empty spaces of the hydrogel scaffold. These trabeculae join at their perimeters with the preexisting bone. We also demonstrate a clear relationship between the composition of the hydrogel and the synthesis of new bone in the defect site. In conclusion, we demonstrate the formation of newly synthesized bone in critical size defects in the rat tibia using a biomimetic hydrogel scaffold without the use of exogenous growth factors.

Purpose of Study: Assessing short and long term eficacy of Extracorporal Shock Wave Therapy (ESWT) as a treatment for recalcitrant plantar fasciitis (PF).

Methods: Prospective follow up of 63 heels among 50 patients with persistent PF patients, (mean age 57.2±10.5); symptoms’ duration 15.8±14.3 months, resistant to non-operative treatment modalities including steroid injections.

All patients underwent thorough physical examination and AOFAS Hindfoot score was obtained before treatment and a follow-up examination one week and one year after applicaton of ESWT course. Pain was assessed by Visual Analog Scale (VAS) relating to six parameters: pain on first step in the morning, maximum pain intensity, pain during prolonged walking, standing, at the end of the day and night pain. ESWT was applied in five consecutive courses of 1500 impulses of 0.32mj/mm² once a week in a routine previously described manner.

Results:. All the six VAS parameters decreased significantly post treatment. The Vas parameter of the first steps in the mornining was the most severe before 8.6±1.8 and after treatment 4.2±2.0 and 1.4±1.9 one year after tretment (p< 0.0001). Night pain was the less intenes before treatment 3.9±3.7 and was nearly eliminated to 0.9±1.6 and 0.2±0.8 after one week and a one year post treatment (p< 0.0001). AOFAS hind-foot Score increased from 49.7±15.8 before ESWT to 87.7±10.9 and 86.3±10.7 one week and year after the courses (p< 0.0001). Three patients couldn’t complete the ESWT course one, one of them with bilateral PF. From those patients two had tarsal tunnel syndrome and one with the tibial nerve first branch which was fassing through the plantar fascia. There were no side effects other than minimal local discomfort during the session time.

Conclusion: ESWT is a safe, efficient treatment modality for resistant PF.

Introduction: Conventional total hip replacement has a high rate of failure in young or high demand patients due to polyethylene wear, therefore, we perform a metal on metal hip resurfacing in these patients. Materials and Methods: The cup is all chrome cobalt alloy, with HA coating and the beads of the porous ingrowth surface are integrated with the substrate metal. The metal head is þxed with low viscosity cement, after careful precise preparation of femoral head.33 hybrid hip resurfacing in 29 patients. Average age was 42.8 years. Results: Harris Hip Score: 34.2 points average preoperatively and 97.1 points at the last examination. The average follow-up was 14.7 month. Discussion: The advantages: Minimal bone resection which makes for easier future revision, normal proximal femoral loading that hence avoidance of the stress shielding present in standard hip replacements, less risk of dislocation with greater range of motion, the physiological biomechanics of the joint is maintained, proprioception is maintained and we have noted that the postoperative recovery is extremely smooth and quick.

The disadvantages: Leg length and neck version cannot be altered. Hip resurfacing is, technically, a demanding procedure.

Contraindications: osteoporosis, varus neck.

Conclusions: Our early results are encouraging. We believe that metal on metal hybrid resurfacing is a legitimate alternative for active patients who require hip arthroplasty.

Introduction: The regulation of balance during upright standing involves continuous muscular activity, associated with body sway. In single stance standing, the base of support is narrower compared to double stance, resulting in an increased body sway and emphasizing the role of individual muscles in regulating the sway motion. In this study, we investigated the effect of Tibialis Anterior (TA) fatigue on body sway during standing on one leg on ten able-bodied subjects.

Methods: Foot ground reaction forces, goniometry of the ankle joint, and EMG of the TA were all measured simultaneously in two tests. Each test lasted 30 sec. During which the subjects were required to stand as still as possible with their dominant leg on a forceplate and the contralateral knee flexed upward at 90 deg approximately, and their hands resting on their waists. The tests were separated by a 4 min isotonic fatiguing effort of the TA, indicated by a significant decrease of the mean power frequency (MPF).

Results: The EGM root mean square (RMS) started off at 45% MVC but, towards the end of the effort, significantly increased to 52% MVC, the latter determined in non-fatigue condition. Compared to the non-fatigue state, the following significant (p< 0.05) sway changes took place in the fatigue state: force RMS increased from 2.61 to 3.90 N and from 3.77 to 5.01 N in the mediolateral (ML) and vertical directions, respectively. The center of pressure (CoP)

RMS in the ML direction increased from 0.57 to 0.68 cm. The EMG RMS in the TA increased from 4.15 to 5.58 and the MPF decreased from 107.6 to 96.7 Hz in the fatigued state.

Discussion: An interesting finding was revealed by comparing the variations of the ankle angle to those of the center of pressure in the anterior-posterior direction taking place during standing. During the non-fatigue test the CoP moved gradually posteriorly, while the goniometer indicated an ankle change towards dorsiflexion. These obviously two opposing trends necessitate compensatory angular adjustments at the knee and/or hip joints. However, during the fatigue test, the posterior excursion of the CoP was accompanied by a consistent change in the ankle, towards plantar flexion. This seems to suggest that in the fatigue state the redundancy of the musculoskeletal system is reduced, increasing the degree of correction between ankle angle and CoP.