Purpose of the study: It is currently accepted that ligament balance should be one of the goals for total knee arthroplasty (TKA) and that this balance should be obtained by correct bone cuts or appropriate ligament procedures. There is however no standard way of assessing this balance. The purpose of this study was to define limit values for knee laxity observed in a series of normal knees and in a series of 54 TKA reviewed at more than ten years.

Material and methods: Laxity in extension of normal knees was measured on forced varus and valgus films using the contralateral knees of patients who had undergone knee surgery for osteotomy or prosthesis implantation. Laxity in extension of TKA knees was measured the first postoperative year and at last follow-up by measuring the decoaptation between the tibial and femoral pieces on single-leg stance films. The change in decoaptation over time was compared with the postoperative and last follow-up goniometry figures, the IKS knee score, the number of loosenings and the number of lucent lines. Multifactorial analysis was considered significant at p< 0.05.

Results: For the normal knees in extension, the medial compartment gap was 2 mm on average (range 1.5–3.5 mm) on the forced valgus images and the lateral compartment gap was 3 mm on average (range 2–4 mm) on the forced varus images. The corresponding angular value was 1° decoaptation on the forced valgus images and 1.5° on the forced varus images. Among the 54 knees with a TKA, the first postperative single-leg stance image revealed a lateral decoaptation _ 3° for 12 knees considered to present laxity, and was _ 2° for 42 knees considered not to present laxity. At last follow-up (13 years on average, range 11–14 years) the 42 knees without laxity remained unchanged without decoaptation, including the 34 normocorrected knees (±3°) and the eight undercorrected knees presenting more than 3° varus (mean undercorection 5°, range 3–7°). The 12 knees presenting postoperative radiographic decoaptation _ 3° showed at last follow-up a significant increase in laxity (p< 0.05) and 2.5° further increase in decoaptation. The increase in decoaptation occurred on normocorrected (n=7) or undercorrected (n=5) knees. This increase in decoaptation was greater with greater residual genu varum. Four groups of knees could be distinguished: normocorrected and stable; normocorrected and unstable; undercorrected and stable; overcorrected and unstable. The number of loosenings requiring revision and the number of progressive lucent lines were significantly greater among unstable knees (two loosenings, and five progressive lucent lines) than among stable knees (no loosening or lucent lines). They were also greater in the group of normocorrected and unstable knees (one loosening and two lucent lines) than in the group of undercorrected and stable knees (no loosening or lucent line). The IKS knee score of stable knees was higher than that of unstable knees irrespective of the correction (p< 0.05).

Discussion: Postoperative laxity in varus with angular decoaptation greater than 3° corresponds to a lateral compartment gap and should be avoided even if the knee is properly aligned postoperatively. If the knee is stable, moderate undercorrection (3–5° varus) does not appear to have an unfavorable long-term effect on knee laxity or on the femoral and tibial pieces.

Conclusion: For knees with constitutional genu varum, moderate undercorrection with a stable knee is preferable to normocorrection at the cost of lost stability.

Background: The Mini C-arm has been heralded as a safer means of fluoroscopy. No clinical data on the use of mini C-arm is available in the literature.

Aim: The purpose of this study was to compare the exposure in clinical practice from the conventional C-arm and the Mini C-arm and scrutinize patterns of exposure.

Materials/methods: Case-Control design. All operations using the mini C-arm were reviewed. Control cases were identical operations using the conventional C-arm. The Sign test was used to detect the number of exposures taken and the dose of radiation.

Results: There were 16 operations with valid case-control pairs. The number of exposures performed was significantly greater for the mini C-arm (p=0.05), but the emitted dose of radiation was significantly smaller (p< 0.001) for the mini C-arm.

Conclusions: The mini C-arm is a safer device for extremity surgery, but the surgeon should be careful to avoid excessive exposures.

Objective: The purpose of this study was to evaluate the effectiveness of surgical reconstruction of posttraumatic deformity. Posttraumatic kyphosis (PTK) causes pain, neurological deficit, sagittal imbalance, progressive deformity, cosmetic and functional deterioration. Its treatment is cause of controversy and technically demanding. There are few reviews in the literature about the results of its surgical treatment.

Methods: From 1995 to 2002 twenty-one patients suffering from posttraumatic thoracolumbar kyphosis were operated. The average follow-up was 3.9 years (range 6 – 1 years). The average age was 38 years (range 23–62): 13 female and 8 male. All patients complained about vertebral pain, 16 located at the apex of the deformity, 2 patients in the lumbar area and 3 patients referred also pain above the lesion. Three patients had irradiated circumferential pain and 4 patients mild neurological deficit. Two patients showed sexual dysfunction. In one patient only anterior approach with allograft reconstruction and anterior plate fixation was performed. In 17 patients simultaneous or staged approach with posterior release, anterior discectomy and allograft reconstruction and posterior compressed instrumentation was performed. In three patients a posterior closing wedge osteotomy was performed

Results: Postoperative pain decreased from 7.5 to 2.8 (VAS). Functional status: preoperative 42.3 % and postoperative 13.8% (Oswestry score). There was no hardware failure. All cases showed solid fusion without significant loss of correction. The average corrected kyphosis was 27.3°. All patients were satisfied with their cosmetic result. No cavity drainage was performed in 2 patients with syringomielia. 1 of 4 patients with neurological deficit did not improve. Two patients had thoracic neuropathic postoperative pain; one of them needed pain clinic treatment until remission. One case had superficial infection. One patient showed a Chylous leakage.

Discussion: Only few works analyze the results of surgical treatment of PTK. The controvesrsy between anterior-aposterior surgery versus posterior closing wedge osteotomy depens of classification of posttraumatic spinal deformities based on three criteria: the region involved, the neurological status and the presence of any sagittal or frontal plane deformities outsides the local kyphosis

Conclusions: Our results suggest that the double approach with anterior allograft and posterior instrumentation shows clinical and radiological efficacy for sagittal posttraumatic deformity. In spite of surgical risk, there have been few complications with a high rate of patient satisfaction.

Study Design: To design and test a new questionnaire to assess depression and other mood states.

Summary of Background Data: Measurement of depression and of other mood states in pain patients has been criticised in recent years on the grounds that most questionnaires were not developed in pain populations and suffer from criterion contamination by somatic items. In addition, there is no accepted measurement for positive emotions which are more than the absence of depression.

Objective: To develop a reliable and brief tool to assess mood in pain patients.

Method: Non-somatic items concerning depression, anxiety and positive outlook were extracted using exploratory factor analysis from commonly used instruments (Beck Depression Inventory and Hospital Anxiety and Depression Scale) completed by over 900 chronic pain patients. Confirmatory factor analysis was used to test the internal structure of the final item set. Items were then reworded and presented as a new questionnaire (the Depression, Anxiety and Positive Outlook Scale: DAPOS) to two new samples: patients attending pain management and patients attending osteopathy. The new questionnaire was compared with several well-known questionnaires (SF-36, BDI, PCS). The structure was calibrated and tested using confirmatory factor analysis on both samples. Finally, a sub-set of patients carried out a sorting task to test for face validity.

Results and conclusion: The DAPOS performed well, indicating that it is a reliable measure of the three mood states with good initial evidence of validity in these samples.

The purpose of this paper is to investigate the relative contribution of each component in the ultimate strength and stiffness of the Evolgate (Citieffe), which is presently a widely used fixation device in DGST ACL reconstruction. The three components of the Evolgate were tested using fresh frozen animal tissue stored at −20° Celsius. Common extensor tendons were harvested from 20-month-old bovine forelimbs. Twenty-four tests were performed for each of the following configurations: six tests using Evolgate complete, six tests using screw alone, six tests using screw and washer and six tests using screw and coil. A randomised t-test was used; differences were considered significant when p< 0.05. The mean strength was: Evolgate complete 1314±194N; coil and screw 700±152N; screw alone 408±86N; and screw and washer 333±93N. There was a significant difference between fixation strength of Evolgate and the other devices, none between screw alone and screw and washer. The mean slippage of the Evolgate was significantly lower than the other devices. The mean stiffness of the Evolgate (269±14 N/mm) was significantly greater than the other devices. On the basis of the results of the present study, the coil appears to be the most important component of the Evolgate, resulting in a significant increase of the fixation strength of the screw. However, it is important to note that, as the washer alone does not improve the strength of the screw, if a washer is associated with a coil a further significant increase in strength and stiffness of the device is observed.

The purpose of this study is to biomechanically evaluate how four different fixation devices (two femoral and two tibial) associated in three different combinations, using cyclic loading with final pull-out test, affect the strength and the stiffness of the femur-graft-tibia complex.

We conducted a controlled laboratory study and tested, using cyclic loading with final pull-out, two femoral devices (Swing- bridge and Endobutton CL) and two tibial device (Evolgate and BioRCI screw) in three different combinations: Group A, EB-Bio RCI; Group B, EB-Evolgate; and Group C, SB- Evolgate.

We used porcine knees and bovine digital extensor tendons and evaluated the stiffness and strength at the final pull-out, and the displacement at the 1st, 100th, 300th, 500th and 1000th cycle.

A t-test was used for statistical evaluation.

There was a statistically significant difference in ultimate failure load between group A and group B (p=0.03) and group A and group C (p=0.0007) but no difference between group B and group C (p=0.72). There was a statistically significant difference in ultimate failure load between group A and group C (p=0.02) and group B and group C (p=0.01) but no difference between group A and group B (p=0.88).

Due to the biomechanical properties of the F-G-T complex the combination of Swing-Bridge and Evolgate seems to be a good alternative when an accelerated post-operative rehabilitation is planned after ACL reconstruction using DGST.

Maintenance of the bone stock is a primary goal in hip surgery. The idea of a resurfacing hip prosthesis had already been proposed in the past without success. The improvement in prosthetic materials, however, has mades it possible to reconsider the use of resurfacing prostheses. We report our experience with the Birmingham hip resurfacing (BHR) prosthesis.

We operated on 58 patients (60 hips, two bilaterally), 31 men, 27 women, with a mean age of 47.9 years (25–76) and a mean follow-up of 27 months (1–42). We used the posterolateral approach with the patient in lateral decubitus. We performed a clinical and radiographic examination before surgery and at 1 and 6 months postoperatively. We recorded a statistically significant improvement in the clinical score at 6 months after surgery, with respect to the preoperative examination. Major complications were two fractures of the femoral neck and one infection. We recorded also peri-prosthetic calcifications in two patients, calcifications of the ileopsoas in two and ileopsoas tendinitis in one.

In conclusion, in our experience, the BHR prosthesis reproduced the biomechanics of the hip and minimised the risk of luxation. The preliminary clinical results are encouraging, also for difficult cases.

The purpose of our study was to determine the effect of 4 weeks and 12 weeks of implantation on the strength of a tendon graft in a bone tunnel using a low-profile fixation device, Evolgate, in an extra-articular ovine model. Moreover, we evaluated the histological changes.

The common digital extensor tendon was detached from the lateral femoral condyle and fixed with the Evolgate device in a 30-mm-long tunnel placed obliquely across the dense metaphyseal bone of the proximal tibia. We performed either biomechanical or histological study. Three sheep were sacrified at time 0 and their posterior limbs were used for biomechanical tests. Six sheep were used for biomechanical tests at time 1 (4 weeks) and at time 2 (12 weeks). The other three sheep were used for histological evaluation after 4 and 12 weeks of implantation. The biomechanical tests included a 50 N preload applied for 10 s and a cyclic load test in 50-N increments until failure to evaluate the ultimate failure load. We used a paired t-test to evaluate the difference between group at T1 and group at T2 with the control group at time 0, respectively. Tests were performed using an electromechanic machine (Zwick-Roell Z010, Zwick-Roell, Ulm, Germany). Data were recorded with dedicated software (Textexpert 8.1, Zwick-Roell).

The biomechanical results show an improvement of about 50% in strength after 4 and 12 weeks post-implantation, respectively. The histological evaluation shows a layer of cellular, fibrous tissue between the tendon and the bone, along the length of the bone tunnel; this layer progressively matured and reorganised during the healing process. The collagen fibres that attached the tendon to the bone resembled Sharpey fibres.

The strength of the interface was noted to have significantly and progressively increased between the second and the 12th week after the transplantation. The progressive increase in strength was correlated with the degree of bone ingrowth, mineralisation, and maturation of the healing tissue, noted histologically.

The use of conventional stems in hip arthroplasty may be difficult in cases of dysplasia, coxa vara or coxa valga, after fracture or proximal femur osteotomy. In fact the morphologic alterations of the proximal femur might require prosthetic components characterised by small size and different neck angles to restore correct joint biomechanics. In these cases we are often compelled to compromise between the ideal implant aneiversion and fit and what we can really achieve. An alternative to conventional prostheses is represented by custom-made prostheses.

For 3 years we have been using the Modulus stem in the treatment of morphologic disorders of the hip. The conic shape of the stem easily fits the different morphologies of the proximal femur, whereas the modularity of the neck makes it possible to correct length, inclination and declination of the femural neck. We studied 59 patients by clinical and radiographic examination before surgery and 1, 3, 6 and 12 months postoperatively. We recorded a statistically significant improvement in the clinical score already at 1 month but this was even better at 6 months after surgery, with respect to the pre-operative examination.

With the use of this prosthesis, the recovery of correct joint biomechanics together with high tribologic standards could improve the implant survival, leading to cost reduction and patient satisfaction.

Secure tendon-to-bone fixation is essential for successful rotator cuff repair. Thus, the biomechanical properties of devices used in rotator cuff repair should be better understood. This controlled laboratory study was performed to evaluate response to incremental cyclic loading of six different anchor-wire complexes commonly used in rotator cuff repair.

Two absorbable anchors 5 and 6.5 mm in diameter and one metallic anchor, coupled with both ethibond or fibrewire (FW) were tested on five pairs of fresh-frozen human cadaveric shoulders. An incremental cyclic load was applied until failure using a Zwich-Roell Z010 electromechanical testing machine. The ultimate failure load and mode of failure were recorded. A t-test was used for statistical analysis.

The FW suture coupled both with absorbable and metallic anchors provides a statistically significant stronger fixation. However, while the metallic anchors in most cases fail due to the slippage of the anchor, absorbable anchors fail due to rupture of the loop. The FW seems to increase the strength of fixation devices under cyclic load both using absorbable or metallic anchors with relevant differences in failure mode (slippage of the metallic anchor and loop failure in absorbable ones). Using a FW suture, the risk of metallic anchor migration might increase.

The increase in knee arthroscopy performed on an out-patient basis, along with the need for cost reduction and a safe and rapid patient discharge, has underlined the importance of adequate anaesthesia techniques. We designed this study to compare efficacy, efficiency and surgeon’s satisfaction of total intravenous anaesthesia with propofol and remifentanil with those of spinal or peripheral nerve blocks for outpatient knee arthroscopy.

A total of 120 patients undergoing elective outpatient knee arthroscopy were randomly allocated to receive total intravenous anaesthesia with propofol and remifent-anil (n=40), combined sciatic-femoral nerve block (n=40) or spinal anaesthesia (n=40). Preparation times, surgeon’s satisfaction, discharge times and anaesthesia-related costs with the three anaesthesia techniques were analysed.

Preparation time was shorter with general anaesthesia (13 min) than with spinal anaesthesia or sciatic-femoral block (15 min; p=0.006). Surgeon’s satisfaction was similar in the three groups. Furthermore, 17 patients receiving peripheral nerve block (42%) and 12 receiving spinal anaesthesia (30%) by-passed the post-anaesthesia care unit after surgery as compared with only two general anaesthesia patients (5%; p=0.01). Discharge from the post-anaesthesia care unit was more rapid after peripheral block; however, stay in the Day Surgery Unit was shorter after general anaesthesia than peripheral or spinal blocks (p=0.026). Urinary retention was reported in three spinal anaesthesia patients only (8%; p=0.03).

Regional anaesthesia techniques reduce the rate of admission and the duration of stay in the post-anaesthesia care unit as compared with general anaesthesia. Peripheral rather than spinal nerve blocks should be preferred to minimise the risk of urinary retention.

Aims: To identify the incidence of neurological deþcit and functional outcome following displaced acetabular fractures. Methods: We carried out a prospective study of 136 patients who underwent skeletal stabilization of displaced acetabular fractures. Patients with sciatic nerve injuries were identiþed, assessed and followed up clinically. Routine EMG and nerve conduction studies were performed post-operatively on all cases with clinical proven neurological lesions to correlate the level, severity of the lesion and monitor progress of recovery. Results: 27 patients (19.8%) have neurological deþcit identiþed preoperatively. In 12 patients where the femoral heads were dislocated posteriorly. 20 were male and 7 were female. The mean age was 33.8 years (range 16–66). 15 patients had associated injuries but none of the patients had injury to the spinal cord. The mean ISS was 12.6 (range 9–34). The mean follow up was 3.4 years (range 1.5–6 years). 13 patients with complete drop foot at presentation. 9 patients had EMG proven double crush lesion. 3 patients had ipsilateral knee injury. 2 patients had intraopearative iatrogenic injury. All 9 patients with double crush syndrome have no improvement in function. Conclusions: Acetabular fractures associated with sciatic nerve injuries are devastating injuries with signiþcant long term morbidity. 50% patients showed improvement with time. Identiþcation of double crush lesion is vital as it is associated with poorer functional recovery as compared to single lesion.

Introduction and Objectives: This is a retrospective study on the treatment of lumbar degenerative disk disease (LDDD) using intervertebral arthroplasty. The lack of uniformity in the treatment of LDDD, persistence of pain even with solid fusion, and the possibility of changes over the fusion site have encouraged us to seek other solutions for this condition. Total intervertebral arthroplasty has been proposed as a possible alternative for selected cases of LDDD.

Materials and Methods: Between November 1999 and July 2002, 16 patients with LDDD were treated surgically using third-generation total intervertebral arthroplasty (Link SB Charité III) with a chromium-cobalt alloy and ultra-high molecular weight (UHMW) poly-ethylene. Average follow-up time was 14 months (6-36 months), and average age was 42 years (35–52). There were 11 females and 5 males. All patients underwent radi-olographic studies, CT scan, MRI, and discography (minimum 2 levels). Indications included LDDD of one to three segments, absence of root tension signs, absence of complete disc collapse, and iconography including concordant discography. LDDD was primary in 11 cases and post-discectomy in 5 cases. Surgery was indicated when at least 6 months of conservative treatment failed to yield results. Blood loss and length of hospital stay were compared to a similar group that underwent posterolateral arthrodesis. Pain, function, and degree of disability were evaluated before and after surgery using GEER (1999) instruments for the evaluation of degenerative lumbar pathology. Increase in height of the posterior intervertebral space and segmentary lordosis were also measured.

Results: Preoperative VAS: 7.8; postoperative VAS: 2.3. Disability index (Oswestry) was 41.3% preoperative and 10.8% postoperative. Average increase in height of posterior intervertebral space was 2.4mm, and mean segmental lordosis was 19.5°, which remained constant through the end of the follow-up period. Average hospital stay was 4.8 days (3–15) compared with 7.5 (5–18) for a group of patients who underwent suspended arthrodesis of L4–L5 with a much smaller quantity of blood loss. No infections were found. Complications: One patient developed an epidural haematoma, which was treated conservatively. Another developed a postoperative retroperitoneal haematoma, which was also treated conservatively. In neither case was there an adverse effect on the outcome of the procedure. One patient showed malpositioning of the prosthetic components on follow-up radiographs, with poor clinical progression at one year postoperative. The patient was treated with posterolateral fusion and right L5 foraminotomy. No infections were seen.

Discussion and Conclusions: Treatment of LDDD with intervertrebral arthroplasty was shown to be effective in the short term, if strict guidelines are followed. Aggressive surgical management is highly inferior to conventional arthrodesis. A longer follow-up period is needed to confirm the validity of this treatment. Technical error in malpositioning of the components in one case caused a poor result.