Surgical treatment of degenerative disc disease (DDD) has been widely modified in the last decade. The clinical evaluation of back pain has been improved by the use of functional scores and VAS. The discography is an adjunct for decision-making, but CT scan and MRI are the keys to evaluate the aging process.

The conservative treatment with physiotherapy and exercise programs is always the first and very useful treatment. Percutaneous therapy like facets injection, laser, IDET, radiofrequency in the disc can be a solution in some specific cases. Their efficacy has been evaluated in different studies and is sometimes controversial but there aren’t contraindications for further treatment and their complication rate is low. Dynamic posterior stabilization devices using pedicular screws and ligament tension band are proposed to try to put the disc in rest and some histological analyzes confirmed this hypothesis. Interspinous devices have been evaluated since many years but there indications need to be established as the literature available doesn’t provide clear indication criteria. Partial disc replacement is a new challenge for DDD. Many devices have in clinical evaluation but only few have prospective studies demonstrating their efficacy. The PDN was the pioneer and as the other in the evaluation process it has to solve the problem of the stability of the device. The last products on the market are promising. The total disc replacement is the last solution before fusion. Many studies including prospective and randomized have demonstrated the efficacy of total disc replacement. The indication is the key point of success. The training to perform the approach safely is mandated. Finally the fusion: anterior, posterior or combined is the ultimate solution to treat DDD. This was the gold standard and is still the most widely used treatment. As a dead end fusion is used only if other solutions cannot be proposed or used. DDD therapy has to be considered with the help of an algorithm including all motion preservation treatment before fusion.

Study Design: Prospective Cohort study.

Objective: To prospectively evaluate the Maverick Lumbar Disc Prosthesis (Medtronic, USA) at one year follow-up.

Methods: Prospective analysis of the Maverick Lumbar Disc Prosthesis implanted in the first 30 consecutive patients for the treatment of single-level degenerative disc disease of the lumbar spine resistant to conservative treatment for more than one year.

Subjects: Sixteen females and 14 males with an average age of 44 years and minimum follow-up of 1 year. The prosthesis was implanted at L4-L5 in 18 patients and at L5-S1 in 12.

Outcome Measures: Oswestry Disability Index (ODI) and Visual Analogue Scale (VAS) preoperatively and at routine scheduled follow-ups. Radiographic analysis included sagittal balance parameters on standing full length lateral radiographs of the spine and range of motion on flexion/extension dynamic radiographs.

Results: Clinical success (ODI improvement > 15), was 82% and 86%, at 6 months and one year follow-up respectively. The VAS showed an improvement in back pain from 7.1 (+/− 2) pre-operatively to 3.0 (+/− 1.8) post-operatively. At one year there were no device related complications. The measured range of motion in flexion-extension ranged from 3 to 12 degrees (mean range of motion, 6 +/− 4 degrees). There was no significant change in sacral tilt, pelvic tilt, or overall lordosis after disc replacement. In one case the ureter was injured during the approach.

Conclusions: The results of total disc arthroplasty presented here compare favourably with results reported in the literature following ALIF. It appears that the disc prosthesis has enough freedom of motion to allow the patient to maintain normal sagittal and spino-pelvic balance with radiographic evidence of normal range of motion. These early favourable clinical results and the influence on adjacent motion segments can be assessed only after long term follow-up.

Introduction: Total disc arthroplasty may offer the same clinical benefits as interbody fusion in symptomatic degenerative disc disease, while providing motion that may protect the adjacent level discs from the abnormal and undue stresses associated with fusion.

Objectives: To prospectively review the preliminary results of the Maverick Lumbar Disc Prosthesis (Medtronic, USA) at maximum 2 year follow-up.

Methods: The first 51 patients (26 M, 25F, age 45.5 mean, 53 levels implanted) were prospectively analyzed. Outcome data included the Oswestry Disability Score (ODI), Visual Analog Scale (VAS) for back and leg pain and SF-36 preoperatively and at routine scheduled follow-ups. Radiographic analysis included sagittal balance parameters and range of motion of the implanted level.

Results: Clinical success (ODI change > 15, FDA) was 82% and 86%, at 6 months and 1 year follow-up respectively. VAS (back) improved from 7.9 (±1.4) to 3.8 (±2.9), and VAS (leg) from (4.6 ± 3.2) to 3.1 (±3.2). All improvements were statistically significant. Two approach, 2 technique and 2 general related complications occurred. Implanted level range of motion ranged from 3 to 12 degrees (mean 6 ± 4 degrees). There was no significant change in any of the sagittal balance variables studied, but a local realignment of the L4-5 L5-S1 segments was found.

Conclusion: These results compare favorably with the short-term clinical outcomes associated with ALIF. It appears that the prosthesis has enough freedom of motion to allow the patient to maintain the natural sagittal and spino-pelvic balance, with normal range of motion. These early favorable clinical results or the influence on adjacent motion segments can be assessed only after a long term prospective randomized study comparing the Maverick to fusion procedures.

Purpose: The objective of this study was to examine the shock absorption capacity of two currently marketed lumbar disc prostheses, a metal-polyethylene prosthesis and a metal-metal prosthesis. Shock absorption capacity, which could be a useful parameter for choosing between implants, has not been examined in the literature.

Material and methods: Two types of implants were tested: the Maverick prosthesis marketed by Medtronic, and the Prodic proposed by Spine Solution. Five implants of each type were tested. The disc prostheses were mounted on a testing device designed to analyse shock transmission by application of a constant force. Force captors were positioned on the upper and lower parts of the implant being tested. The force delivered and the force perceived on the opposite side of the implant were recorded simultaneously. The implant was submitted to a static loading force of 350 N to which was added a 100 N oscillating vibration force delivered at a frequency varying from 0 to 100 Hz. A supplementary 250 N shock was also applied every 10 s. The spectrum and frequency of each input and output were recorded. Vibration and transmission of the shock though the implant were defined as the ratio of the output over input spectra. Measurements were taken for all frequencies between 0 and 100 Hz. Phase deviation was calculated to characterise the shock absorption effect.

Results: The phase deviation between the input and the output signal was less than 10 for both prostheses. Under loaded oscillating vibration, shock transmission was greater than 99.8% for both implants. In the 1–100 Hz frequency interval, the difference in shock transmission was less than 0.3±0.1% between the two implants. More than 98% of the supplementary 250 N shocks were transmitted by both implants. The difference between the two implants was thus less than 0.8% and can be considered negligible since the machine’s test sensitivity was 0.5%.

Conclusion: The two implants tested exhibited the same capacity to absorb and transmit vibration and shocks. Shock absorption capacity was close to zero or at least less than the sensitivity threshold of the testing device. This degree of freedom is not sufficient to use shock absorption capacity as an argument for choosing between the two implants currently available.

Purpose: Intersomatic L5-S1 arthrodesis is a common procedure in orthopaedic surgery of the spine. Two approaches are generally proposed: the anterior trans or retroperitoneal approach and the posterior approach via the spinal canal or laterally. We conducted an anatomic animal study to examine the feasibility of a new approach to the L5–S1 disc.

Material and methods: Five anatomic specimens were used. The approach consisted in introducing via posterior laterosacral access a blunt 5 mm trocar into the sacrococcygeal joint. A 2 cm incision was made to identify the anterior aspect of the sacrum. Anterior and lateral scopic control was used to follow the progression of the trocar. The guide was medialised and slid into the median part of the sacrum. A larger tube with an oblique end was slid over the guide and impacted on the inferior border of the S1–S2 disc. The blunt trocar was then removed and the tube was impacted into the S2 bone under scopic control. A hollow bit was then inserted into the tube to perforate S2 and reach the L5-S1 disc. Angled instruments allowed nucleoctomy without injuring the annulus. All specimens were then explored anteriorly. The technique was tested on five 40–50 kg living pigs. After inserting the hollow bit, laparoscopy was performed to visualise the trajectory of the tube and search for possible complications.

Results: The anatomic study was conducted with the animals placed in a ventral position. The blunt trocar easily detached the presacral infraperitoneal region without any perforation of the neighbouring organs (sigmoid, colon). The presacral membrane was fragile in two cases but appeared to have been weakened by prior intra-peritoneal surgery due to the presence of pseudomembranes. It was possible to achieve perforation of S1 and partial L5–S1 discectomy in all cases. Nucleoctomy was difficult due to insufficient instrument design. There was no problem in inserting the trocar and reaching the L5–S1 disc in any of the piglets.It was sometimes difficult to impact the tube into the S1 bone because of the small angle between the sacrum and the lumbar spine. Laparoscopy revealed a small pre-sacral haematoma in four cases without significant bleeding. In one case, the haematoma was much larger and related to arterial or venous bleeding from presacral vessels. Insertion of the trocar was difficult. The instrument slid toward the promontory probably causing injury to a branch of the sacral vessels which have a large diameter in the piglet.

Discussion: This anatomic study demonstrated the feasibility of a new approach to the L5–S1 disc. This approach could be an interesting alternative in several indications: revision surgery for nonunion after other methods, treatment of certain types of spondylolisthesis. For partial prosthetic replacements (nucleoplasty) this approach would have the advantage of avoiding the need to open the annulus, the principal element of disc stability. Other trials would be necessary to design adequate instrumentation, but this new approach appears promising because it involves a minimally vascularised area. Video assistance for the trocar would help optimise presacral dissection.

Purpose: We propose a simple surgical treatment with sustained efficacy for chronic symptomatic acromioclavicular instability.

Material and methods: Dissection of ten cadaver specimens (20 shoulders) enabled a detailed biometry of the acromiocoracoid ligament (ACCL) with measures of motion and clavicular fixation. We were also able to measure tear resistance with a dynamometer. The proposed surgical technique was designed from Weaver-Dunn reconstruction as modified by Bircher. Briefly, acromioplasty is used to dis-insert the ACCL which is folded back on the clavicular resection border then fixed by screws or wires.

Results: The size of the acromioplasty section varied from 18 to 25 mm in diameter. The ACCL had a quadrilateral aspect: mean anterior length 37.7 mm, mean posterior length 25.6 mm, mean middle (coracoid) width 16 mm, mean lateral width 22.3 mm and mean thickness 1.55 mm. The fold angle was 68° on average giving 10.8 mm in height and 21.8 thickness. The coracoclavicular distance varied from 15.7 mm to 50.1 mm. Mean tear force was 11.5 daN.

Discussion: Posttraumatic osteoarthritis of the unstable acromioclavicular joint requires resection of the lateral quarter of the clavicle using the Baccarani technique which should be completed by a stabilisation fixation. The Weaver-Dunn technique appears to be insufficient for Rockwood stage IV and B chronic instability. The distance between the anterior border of the coracoid and the posterior border of the clavicle is within the reach of the length of the acromiocoracoid ligament. The available length allows tension adjustments before fixation, which should be performed preferably using a wire fixation or a 3.5 compression screw set on a washer to achieve satisfactory stability and good pull-out resistance.

Conclusion: Biometrics of the ACCL and the width of the acromioplasty and clavicular osteotomy demonstrate several possibilities for regulating the fixation which can thus be adapted to the morphology of each case while assuring good compression and solid fixation necessary for excellent long-term results.

Purpose: Cage fusion of the L5–S1 segment is a controversial issue due to the weak stabilisation of the spine during extension and axial rotation. Complementary fixation appears to be needed to improve stability, but the presence of the bifurcation of the great vessels is an anatomic limitation. We studied the anatomy of this area to examine the feasibility of anterior plate fixation.

Material and methods: According to the recognised anatomic references (Rouvière, Bouchet and Cuilleret, Louis), a 33-mm safety zone was described at the aortoiliac and iliocaval bifurcation. This space free from contact with the greater vessels lies in front of the L5–S1 disc. Pre-operative angio-MRI was used to assess the size of this safety zone. A triangular anterior plate was designed for arthrodesis (Pyramid Sofamor Danek, USA). An L5–S1 arthrodesis was performed in 15 consecutive patients using this plate. Follow-up was one year. A video-assisted anterior retroperitoneal approach was used in all cases. The Prolo and Oswestry scores were used for the preoperative and last follow-up evaluations.

Results: According to the anatomic study and the MRI views, 89% of the patients had a sufficient safety zone for plate fixation. The method was contraindicated in two patients who had a low bifurcation. Angio-MRI was found to be simple and reproducible. The MRI analysis was confirmed at surgery (no false negatives). The plate was successfully implanted in 15 patients with no contact with the great vessels. There were no serious complications (vascular, neurological, urological, digestive). The economic Prolo score was improved from 2.7 to 4.2 and the functional score from 2.6 to 4.3. The Oswestry score improved 33%. The rate of clinical success was 93% (14/15 patients).

Discussion and conclusion: Implantation of an anterior plate for L5-S1 fusion is feasible. The key points are: 1) rigorous preoperative evaluation of the greater vessel bifurcation; 2) anatomic plate design; 3) appropriate surgical technique. The risk of retrograde ejaculation is related to retraction of the hypogastric plexus and should be investigated with a prospective study. This osteosynthesis technique can avoid secondary operations for fixation with pedicular or transarticular screwing.

Purpose: Retrograde ejaculation after anterior approach for intersomatic L5-S1 arthrodesis is one of the most serious complications for young patients. The risk is related to the destruction of the hypogastric plexus during exposure of the lumbosacral segment. The rates reported in the literature vary from 0.42 to 5.9%. The purpose of this study was to compare the incidence of retrograde ejaculation in a prospective study of two groups of patients undergoing L5-S1 fusion via a trans-peritonial or retroperitoneal approach.

Material and methods: One hundred forty-six male patients underwent L5-S1 arthrodesis. Group A included 116 patients for whom a video-assisted retroperitoneal approach was used. Group B included 30 patients for whom a video-assisted transperitoneal approach was used. Patients were questioned concerning the presence or not of retrograde ejaculation at the preoperative examination then at 3, 6, and 24 months.

Results: Among the 146 patients, six exhibited retrograde ejaculation at three months. Two (1.72%) were in the retroperitoneal group (group A) and four (13.35) were in the transperitoneal group (group B). This difference was significant (Fisher test, p = 0.0015). Retrograde ejaculation regressed in two of these six patients at one year, one in group A and one in group B. At the end of the study with two years postoperative follow-up, four patients exhibited persistent retrograde ejaculation, one in group A (0.86%) and three in group B (10%). The difference was statistically significant (Fisher test, p = 0.025).

Discussion: This study provides to our knowledge the only prospective data available concerning the risk of retrograde ejaculation in patients undergoing anterior L5-S1 arthrodesis. The risk was significantly higher with the transperitoneal approach than the retroperitoneal approach (10% versus 0.86%).

Purpose: Nonunion of the surgical neck of the humerus can occur after orthopaedic or poorly-adapted surgery after displaced subtuberosity or cephalotuberosity fracture. The purpose of this study was to report functional and radiographic outcome after treatment with shoulder prosthesis.

Material and methods: Twenty-two patients who had a non-constrained shoulder prosthesis were included in this retrospective multicentric study. Mean age was 70 years and mean follow-up was 45 months (range 2 – 9 years). The initial fracture had two fragments in six patients and was a three-fragment fracture involving the head and the tubercle in thirteen and a four-fragment fracture in three. Orthopaedic treatment was given in ten cases and surgical osteosynthesis was used in twelve. Time from fracture to implant insertion was 20 months. The deltopectoral approach was used for 21 humeral implants and one total shoulder arthroplasty (glenohumeral degeneration). The tuberosities were fixed to the cemented humeral stem and a crown of bone grafts were placed around the nonunion of the surgical neck. All patients were reviewed after a minimum of two years and assessed with the Constant score and x-rays.

Results: The absolute Constant score improved from 23 reoperatively to 39 postoperatively with an anterior elevation of 53° to 63°. Pain score (from 3 to 9, p = 0.001) and external rotation (from 13° to 28°, p = 0.01) were significantly improved. Forty-five percent of the patients were satisfied and 55% were dissatisfied. The type of initial treatment, type of initial fracture, and time before implantation of the prosthesis did no affect final outcome. The complication rate was 36% (eight patients), and led to five revision procedures. The radiographic work-up disclosed six cases of persistent nonunion of the greater tuberosity, two proximal migrations of the prosthesis, and one humeral loosening.

Conclusion: Outcome of shoulder prosthesis for sequela after fracture of the proximal humerus with nonunion of the surgical neck is poor. No improvement in anterior elevation, force, or motion was achieved. Shoulder prosthesis for sequelae of fracture of the proximal humerus with nonunion of the surgical neck should be considered as a “limited-objective” indication only providing beneficial pain relief.

Purpose: Collapse or necrosis of the head of the humerus after fracture of the proximal humerus can be an indication for shoulder arthroplasty. The poor results classically reported have led to a search for factors predictive of the anatomic and functional outcome after arthroplasty for fracture sequelae.

Material and methods: Among the 221 Aequalis prostheses implanted for the treatment of sequelae after fracture of the proximal humerus, 137 (62%) developed post-traumatic avascular osteonecrosis of the humeral head with a deformed callus of the tuberosity. Head tilt was in a valgus position in 83 shoulders and in a varus position in 54. Mean age was 61.49 years. The initial fractures were subtuberosity fractures in 20% of the cases, three-fragment fractures in 32%, and cephalobituberosity fractures with four fragments in 48% of the cases.Twenty-five percent of the patients had undergone initial osteosynthesis. The rotator cuff was repaired in 4.5%, and two osteotomies of the less tuberosity and four osteotomies of the greater tuberosity were performed at implantation. Pre- and postoperative clinical and functional outcomes were assessed with the Constant score and a function index composed of eleven usual movements.

Results: Mean follow-up was 44 months (24–104), with a mean 42° gain in anterior elevation and a 29° gain in external rotation. The gain in the Constant score was +32 points (mean score 61), and +43% with the weighted score. The four subscores (pain, motion, activity, force) improved two-fold. Analysis of the eleven usual movements demonstrated recovery in 88% of the patients. The subjective satisfaction index was 86%. The mean Constant score improved significantly more after total arthroplasty (67 points) than after humerus prosthesis (55 points). Complications (per- or postoperative mechanical problem, infection, neurological disorder) or the need for revision were unfavourable elements.

Discussion: Deformation and deviation of the tuberosities, especially the greater tuberosity, often leads to osteotomy during the implantation procedure. In this series, osteotomies were exceptional and functional outcomes showed that deviated tuberosities could be preserved without having an unfavourable effect on functional prognosis. Much on the contrary, the absence of a tuberosity osteotomy simplified the operative procedure and produced much better functional outcome than observed in earlier studies. The rate of complication for secondary prosthetic implantation is not negligible (15%) and a simplified procedure without osteotomy is a useful criterion. Furthermore, rehabilitation may be started earlier after implantation when it is not retarded by osteotomy bone healing, found to be an unfavourable factor.

Conclusion: Implantation of a shoulder prosthesis after collapse or necrosis of the head of the humerus after proximal fracture with varus or valgus impaction has provided good functional outcome without tuberosity osteotomy since the deformation of the tuberosity is generally well tolerated.

Purpose: Thoracoscopic spinal surgery may be less aggressive than classical open surgery. We relate our experience over the last five years, analysing complications observed.

Material and methods: Between 1995 and 2000, 68 patients underwent thoracoscopic spinal surgery. There were 34 men and 34 women, mean age 30.2 years (13–69). We analysed indications, preoperative anaesthesia parameters, peroperative and postoperative parameters and pulmonary, vascular, neurological and instrumental complications.

Results: Indications were: metastatic compression in three patients, disc herniation in eight with five calcified discs, fracture in 25, anterior release for scoliosis in 32 with inter-somatic graft in 20. Mean duration of the hospital stay was 19.6 days (7–48). There were three fractures with lung contusion that were excluded from the analysis although thoracoscopic surgery was possible. The analysis thus included 61 right and four left thoracoscopies. Four to nine trocars were used. There were three cases of intercostal nevralgia. Operation time depended on the underlying disease: 18 min for scoliosis, 2 hr 40 min for fractures, 4 hr 15 min for discal herniation (2 h 20–7 h 15). Blood loss was less than 200 cc for scoliosis, a mean 533 cc for fractures, and 800 cc for metastases. There were no pulmonary, vascular or instrumental complications. The image amplifier was used to monitor all osteosyntheses. We had one patient whose neurological situation worsened after resection of a transdural calcified thoracic herniation. Stay in the intensive care unit after surgery was 3.4 days, the drain was removed at 3.26 days and had collected 1240 cc. Postoperative paint was assessed for patients who had undergone thoracoscopy alone and who had no other disease (19 fractures and 8 herniation cases). level three antalgesics were required for 3.2 days. There were no vascular complications or signs of phlebitis. One residual atelectasia of the lower right lobe occurred in a female patient with major traumatic contusion, and pleural effusion was observed in three. One patient developed a contralateral pneumothorax that was punctured after release of major scoliosis (Cobe 92°). Residual pleural effusion after withdrawing the drain was aspirated at 48 hours. There were no infections.

Discussion: Thoracoscopy allowed the planned procedure in all patients. Blood loss was much lower than with classical open surgery. Pain was controlled better and the cosmetic effect was exceptional. Function was recovered rapidly by fracture patients. the quality of the anterior release for the scoliosis patients was equivalent to that obtained with classical techniques.

Conclusion: The complication rate was lower than that usually observed for similar procedures using classical techniques.

Purpose: We conducted a prospective preliminary study of ten cases of surgical repair of massive rotator cuff tears using a free quadriceps bone-tendon transplant. All procedures were performed between May 1998 and May 2000.

Material and methods: The series included seven men and three women (mean age 51 years 9 months). The dominant limb was involved in nine cases. Six of the patients were working. Mean duration of symptoms was 15 months (6–36 months). Mean preoperative Constant score was 49.1/100 points. The three most frequent signs were daily pain, limited amplitude, and loss of force. A MRI was obtained in nine cases and an arthroscan in one. There was a full-thickness tear of the rotator cuff with proximal retraction in eight cases and intermediary retraction in two. Fatty degneration (Goutallier-Bernageau) was basically grade II for the supraspinatus, and grade III for the infraspinatus. At MRI the tear measured more than 16 cm². Acromioplasty was performed in all cases, tenotomy and long-biceps tenodesis in seven. Sutures were made with Mersuture n° 2 using the Mason-Allen technique along the tear contour. The superficial portion of the quatriceps tendon was harvested via a longitudinal prepatellar incision. The quadriceps tendon was harvested with the trapezoidal patellar bony attachement. The free quadriceps tendon flap was sutured to the borders of the cuff and a bony tunnel was made to impact the bony attachment. Postoperative immobilisation was achieved with an abduction sling and a removable flexion brace for the knee. All patients participated in the centre’s rehabilitation programme and were reviewed at consultation. An MRI was obtained for five patients with the longest follow-up.

Results: Mean follow-up was 18 months. Mean Constant score at last follow-up was greater than 70 points. Mean force was less than 5 kg. The MRI obtained in five cases demonstrated a normal tendon with no signs of necrosis. There was one tear of the quadriceps tendon at the knee. This patient experienced persistent fatigability at 12 months.

Discussion: Treatment of full-thickness tears of the rotator cuff remains problematic, particularly in young active patients. Acromioplasty and bursectomy only provide pain relief. There is an ascension of the humeral head with an excentrated scapula. Classical transosseous reinsertion is not possible when there is major retraction. Certain teams advance the supraspinatus and the infraspinatus. Deltoid flaps only provide pain relief by their interposition in the subacromial space. Tendon transfer using the rectus is highly invasive and difficult to perform. The quadriceps tendon transplant is resistant and integrates perfectly in this reconstruction.

Conclusion: Repair of massive full-thickness rotator cuff tears in young patients with limited fatty degeneration remains a difficult challenge. For these patients, we propose repair using a free quadriceps bone-tendon transplant.