The treatment of rotator cuff arthropathy due to irreparable massive rotator cuff tear is still challenging. We performed reverse total shoulder arthroplasties for 2 cases of cuff tear arthropathy. The short term follow-up after the surgery reveal excellent results by ASES and UCLA score. However, these results still require long term follow-up and the study about implant design for the shoulder anatomy of the Koreans.

The purpose of this study was to investigate the efficacy and fusion rates of a unilateral pedicle screw construct supplemented with a translaminar screw in transforaminal lumbar interbody fusion (TLIF). The construct was used with an aim of providing suitable spine stiffness with minimal implant load for spinal fusion.

Nineteen consecutive patients who underwent single level TLIF were included in the study. All patients had posterior spinal instrumentation using a unilateral pedicle screw construct with a contralateral translaminar screw. Patients were assessed preoperatively and at two, six, twelve and twenty-four weeks following surgery and at the end of one and two years. At every visit Oswestry disability index score,Visual analogue scale for pain and a pain diagram were recorded. A radiographic exam was also conducted and CT scan was done if there was concern about fusion.

The average follow up was twenty-four months. There were twelve males and seven females with an average age of forty-eight years. All patients went on to clinical and radiographic union. Sixteen of nineteen patients had significant clinical improvement on VAS for pain, Oswestry scores and pain medication. Three patients had recurrence of radicular pain on the side of the TLIF leading to reexploration. In all three patients solid fusion was observed but scar tissue was evident and symptoms resolved following redecompression of the foramen.

The biomechanical competence of a construct is evidenced by successful fusion. With the advent of minimally invasive techniques to achieve spinal fusion the goal is to use minimal instrumentation without compromising on the final stiffness of the spine. The construct of unilateral pedicle screws supplemented with a trans-laminar screw led to fusion in all our cases. It requires lesser soft tissue dissection and the posterior implants are 56% cheaper.

The first metatarsophalangeal (MTP) joint is the key joint of the foot in terms of function during gait. Various replacement toe joint prostheses are commercially available but unlike other replacement joints such as the hip or knee, few simulator based studies have been conducted to evaluate the performance and reliability of these prostheses. Presented are results obtained using a newly developed and validated multi-station MTP joint test-rig that is able to simulate the natural biomechanics of the toe joint. The developed simulator is a multi-station computer controlled electro-pneumatic metataso-phalangeal joint simulator that applies dynamic loading and motions commensurate with the walking gait cycle. This involves the combination of plantar-dorsi flexion range of 32 degrees, 5 degrees of inversion/eversion and toe-off dynamic loading peaking at up to 820 N. Presented are the validation and in vitro test results of MTP joint simulations carried out on silastic and articulating metal and polymer designs of MTP prostheses. Despite being subjected to a reduced loading regime of 300 N peak force, the silastic prostheses were found to perform poorly in the simulator, ultimately failing due to a combination of fatigue crack growth and joint collapse. This behaviour and failure mode was consistent with that of ex vivo origin silastic MTP prostheses examined and provides confidence in the validity of the simulator.

Introduction: The purpose of this study is to evaluate the clinical and radiogra phic outcome of patients with secondary osteoarthritis of the hip, who underwent custom-made cementless THA.

Methods: Between January 1994 and June 1997, 98 prim ary cementless custom-made THA’s were performed in 76 patients with secondary osteoarthritis and reviewed at mean 6 years follow-up (range: 4 – 7.5 years). Nine patients had a previous femoral osteotomy. There were 69 females and seven males. The mean age at operation was 54 years (40 – 73 years). Custom-made, 125 mm-long, titanium femoral components with blasted surface were fabricated based on the computerized tomography.

Results: The mean Harris Hip Score improved from 43 to 95 points. 97 patients (99%) had more than 80 points for total score, and 2 patients (2%) had thigh pain at the latest follow-up. Radiographically, 86 hips (87%) showed obviously extensive bone ongrowth onto the middle part of the stem while 8 hips (9%) showed stable fibrous fixation. Four hips (4%) were unstable: more than 2 mm subsidence in 2 hips and more than 2 degrees varus migration in 2 hips. Of these 4 hips, 2 had intraoperative cracks of the poximal femur and 2 had varus positioning of the stem.

Discussion and conclusion: Cementless THA has been advocated to enhance fit and fill of variable hip geometry. However, some clinical studies failed to show that custom implants significantly improve clinical success or implant longevity because their surface finish was not optimal. Custom-made titanium femoral components with blasted surface showed good clinical results. The reasons for radiolographical failures were because of intraoperative technical errors and these might be derived from 125 mm-long stem with maximum canal fill. A shorter stem may be an option because it may improve the feasibility of stem insertion and the distal fill.

Aims: To evaluate the early midterm outcomes of primary total hip arthroplasty (THA) using Hydroxyapatite (HA)-coated on smooth surface acetabular component with 28 mm metal head on polyethylene liner articulation. Methods: Seventy primary THA in 63 patients with HA-coated acetabular component were performed consecutively between June 1993 and August 1996. Fifty-four cases were eligible for follow-up of average 71 months (48–104) and the mean age of index operation was 49 years (23–71). The clinical results were analyzed by modiþed Harris hip score, and the radiologic evaluation in terms of stability, polyethylene wear rate (Dorr method), osteolysis around acetabular component was done. Results: Mean Harris hip score improved from 50.9 to 82.2 at the last follow-up. Excellent or good results were found in 38 cases (70%). Eight cases (15%) were unstable radiologically. Pelvic osteolysis was found at 18 cases (33%). The mean polyethylene wear rate was 0.146 mm/year (0.01–0.45). Wear rate of hip dyaplasia was greater than osteonecrosis signiþcantly (p< 0.05). Seven cases (13%) were revised (5 mechanical failures, 2 deep infections). Any bone ongrowth was not found during revision surgery for loose components. Complications included 5 heterotrophic ossiþcations, 2 deep infections, and 1 nonrecurrent dislocation. Conclusion: Primary THA using HA-coated on smooth surface acetabular component showed unsatisfactory clinical results, accelerated polyethylene wear rate accompanying high incidence of osteolysis, and high loosening rate due to lack of bony ongrowth at early midterm.

Introduction: The results of transtrochanteric rotational osteotomies for osteonecrosis of the femoral head were reviewed.

Materials and Methods: The results of 26 transtrochanteric osteotomy in 24 patients with Ficat stage II or stage III osteonecrosis of the femoral head performed between April 1994 and June 2001 were evaluated. Osteotomy was primarily conducted on patients younger than 50 years of age when the necrotic lesion was at least 30% of the whole femoral head and was located at the superior aspect. Twenty-three hips in 22 patients were available for clinical and radiological follow-up at 59 months (range, 24–109 months). The average age of the patients at the time of the index procedure was 35 years (range, 23–51 years). The results were considered successful if there was no radiologic failure (progression to necrosis, further collapse) or clinical failure (the need for total hip arthroplasty).

Results: Eighteen (78%) hips had a successful result. Two hips showed progressive varus deformity and were treated by valgus osteotomy. One hip survived and one hip underwent a Girdlestone operation followed by total hip arthroplasty to treat an associated deep infection. Four other hips were also subsequently treated with total hip arthropalsty because of head collapse with severe varus deformity or neck fracture in three hips and infection after osteotomy in one hip.

Discussion: Our results suggest that transtrochanteric osteotomy is a dependable procedure in the treatment of a large lesion even in the later stages of osteonecrosis of the femoral head, which is especially true for patients under the age of 50 years.

Introduction: In order to investigate the relationship between the degeneration of the acetabular cartilage and the radiological staging of osteonecrosis of the femoral head, the following study was performed.

Materials and Methods: Acetabular cartilage with sub-chondral bone was taken from the superior dome from 34 hips from 30 patients undergoing total hip arthroplasty due to osteonecrosis of the femoral head. The specimens were stained with hematoxylineosin and safranin-O, and were evaluated as to the thinning of cartilage, fibrillation, clefts, and proliferation of chondrocytes. There were 18 females and 12 males with an average age of 49 years. We used the radiological staging system proposed by the working group of the Specific Disease Investigation Committee under the auspices of the Japanese Ministry of Health, Labor and Welfare. There were eight hips in stage IIIA disease (collapse of the femoral head less than 3 mm), 19 hips in stage IIIB disease (collapse 3 mm or greater), and seven stage IV disease hips.

Results: All 34 specimens showed histological abnormalities. In eight stage IIIA hips, six hips were mild and two were moderate histological degeneration. In 19 stage IIIB hips, five hips were mild, six were moderate, and eight had severe arthrosis. Seven stage IV hips had severe arthrosis.

Discussion: Although the radiographs cannot demonstrate early degeneration of cartilage, degenerative changes were present in all stage III hips. Histological degenerative changes in stage IIIB hips were more severe than those in stage IIIA hips. These findings should be kept in mind in treating patients with osteonecrosis of the femoral head.

Study Design: We describe innovative minimally invasive Israeli made Expandable Spinal Fusion System for lumbar spinal fusion, in patients with all caused of mechanical back pain: Degenerative Disc Disease (DDD) at one or two levels from L2–S1, up to Grade l spondylolysthesis. The purpose of the study was to provide a preliminary evaluation of the safety and efficacy of the Expandable Spinal Fusion System in establishing vertebral stability and fusion, and in improving the quality of life of the patients.

The relatively large diameter of currently used cages dictates extensive manipulations, damaging structures that are crucial for spinal stability.

The Expandable Spinal Fusion System, is 5 mm in diameter in closed configuration, applied in a minimally invasive technique, through a 6mm entering opening by an open or percutaneous posterior procedures. Once in position, its dimensions are increased to a precut size in a controlled procedure. Thus, this system maintains the integrity of facet joints, with no or minimal laminectomy, and minimal damage to the surrounding tissues.

Methods: Data were collected in a series of 60 patients with DDD in levels L3–S1. The patients wee operated in the open posterior approach with or without Pedicle Screws and percutaneous posterolateral. Both end-plates faces were treated by special curettes and partially removed. Posterior iliac bone graft was used and 2 tubes device were introduced to the inter-somatic space under direct vision controlled by X-rays C-Arm intensifying magnification.

Data: The implantation approach was posterior in 52 patients, anterior in 2 and percutaneous in 6 patients. Maximal follow up period is 12 months. Patients follow up was completed according to investigational protocol mandate follow up visit at 1.5, 3, 6, 12 months postoperatively. The main at the time of the surgery was 52 years old. 57 underwent surgery at one level as follows: 3 at L3-L4, 32 at L4-L5, and 21 at L5-S1, and 3 underwent surgery at two levels.

Patient questionnaire pain and quality of life was evaluated using the Oswestry questionnaire and VAS measurement. The patient fill those pre-operatively and at each follow up visit.

Results: Although follow up period is short according to preliminary data, the Expandable Spinal Fusion System has proved to be safe, effective, as well as easy to handle for treating all cases of mechanical back pain: DDD. There was no neurological injury, no infection, no death and no worsening of clinical symptoms. There was no breakage or migration of the implant at the last follow-up. Flexion-Extension X-ray show good stability. VAS score for pain dropped from 8 pre op to 2.6 in average 3 months post-op.

It has been shown that the bone, nerve, tendon, and muscle can generate new tissue when a leg is lengthened. In this study we have examined the muscles to see whether the proliferative response occurs uniformly along the fibres or whether it is a disproportionate occurrence, and also to see whether the muscles of animals of different age responded differently.

In five adult (more than 25 weeks) and five young (8 to 9 weeks) New Zealand White rabbits, a mid-diaphyseal tibial osteotomy was created and stabilised with an Orthofix (M-100) external fixator. After seven days, lengthening was carried out at a rate of 1.6 mm/day until a 20% increase in the tibial length had occurred. One hour prior to sacrifice, all of the animals were injected with bromodeoxyridine (BrdUrd, 40mg/kg).

Proliferative response of muscle tissue was assessed by measuring the positive staining index (PSI) of BrdUrd in a two-step indirect immunohistochemistry using the monoclonal antibody Bu20a. We accomplished this staining in transverse sections (between the proximal and middle third, and between the middle and distal third of the muscle belly) and in longitudinal sections along the proximal, middle and distal third of the myotendinous junction (MTJ) of the lengthened flexor digitorum longus muscle belly. The opposite limb was used as a control for each animal.

All of the muscles showed a proliferative response that was significantly higher on the experimental side. There was no difference between the PSI of the proximal transverse sections and the distal transverse sections. The young animals demonstrated significantly increased PSI in all sections compared with the adult animals (immature distal transverse section PSI: 4.91%; mature distal transverse section PSI: 1.67%). The PSI of the longitudinal sections of MTJ showed significantly higher values than in the muscle belly (PSI at the MTJ in adults: 5.23%; PSI at the MTJ in the young: 13.2 %). The PSI result was increased at the distal third of the MTJ in mature and immature rabbits (p0.05).

The muscles show a proliferative response to elongation forming new muscle tissue. The proliferative reaction to lengthening is far greater in the muscles of growing animals compared to adults. The myotendinous junction demonstrates much more intensive proliferative activity than the muscle belly. The distal third of the myotendinous junction shows the highest PSI results. The results of this study help to interpret the results of the animal model for clinical studies and also indicate an advantage in carrying out lengthening on young individuals.