Correct femoral tunnel position in anterior cruciate ligament reconstruction (ACLR) is critical in obtaining good clinical outcomes. We aimed to delineate whether any difference exists between the anteromedial (AM) and trans-tibial (TT) portal femoral tunnel placement techniques on the primary outcome of ACLR graft rupture.

Adult patients (>18year old) who underwent primary ACLR between January 2011 – January 2018 were identified and divided based on portal technique (AM v TT). The primary outcome measure was graft rupture. Univariate analysis was used to delineate association between independent variables and outcome. Binary logistic regression was utilised to delineate odds ratios of significant variables.

473 patients were analysed. Median age at surgery was 27 years old (range 18–70). A total of 152/473, (32.1%) patients were AM group compared to 321/473 (67.9%) TT. Twenty-five patients (25/473, 5.3%) sustained graft rupture. Median time to graft rupture was 12 months (IQR 9). A higher odds for graft rupture was associated with the AM group, which trended towards significance (OR 2.03; 95% CI 0.90 – 4.56, p=0.081). Older age at time of surgery was associated with a lower odds of rupture (OR 0.92, 95% CI 0.86 – 0.98, p=0.014).

There is no statistically significant difference in ACLR graft rupture rates when comparing anteromedial and trans-tibial portal technique for femoral tunnel placement. There was a trend towards higher rupture rates in the anteromedial portal group.

Introduction

The ideal method of fixation for femoral components in total hip arthroplasty (THA) is unknown. While good results have been reported for cemented and uncemented components, there is relatively little published prospective data with twenty years or more of follow up.

Results of the Furlong femoral component have been presented at an average of 17 years follow up. We have extended this follow up period to an average of 22.5 years with a minimum of 22 years and a maximum of 25 years.

A reduced range of movement post total knee replacement (TKR) surgery is a well recognised problem. Manipulation under anaesthesia (MUA) is a commonly performed procedure in the stiff post operative TKR. Long term results have been variable in the literature.

We prospectively followed up 48 patients since 1996 from one centre, over an average of 7.5 years, (range 1 to 10 years) and report on the long term results.

The mean time to MUA post TKR was 12.3 weeks (range 3 to 48). Pre MUA, the mean flexion was 53°. The mean immediate passive flexion post MUA was 97°, an improvement of 44° (Range 10° to 90°, CI < 0.05). By one year, the mean flexion was 87°, improvement of 34°, (range −15° to 70°, CI< 0.05). At ten years the mean flexion was 86°.

We found no difference between those knees manipulated before or after 12 weeks. In addition there was no difference found in those knees which had a pre TKR flexion of greater or less than 90°. There were no complications as a result of MUA. However, one patient was eventually revised at two years secondary to low grade infection.

Our findings show that MUA is safe and effective method at improving the range of motion in a stiff post operative TKR. The improvement is maintained in the long term irrespective of time to MUA and range of motion pre TKR

Introduction

We report the outcomes of minimally invasive technique for posterior lumbar interbody fusion (PLIF) procedure using Hollow Modular Anchorage (HMA) screws supplemented by routine pedicle screw fixation (Dynesis).

Objective

From our series of 570 Dynesys flexible stabilisation procedures, we studied two prospective series of patients with a minimum one-year follow-up comparing uncoated and hydroxyapatite-coated (HA) screws.

Purpose of Study

To review the medium-term results of the Dynesys stabilisation system used in 113 consecutive patients with discogenic back pain.

We have studied two matching cohorts of patients treated by Dynesys flexible stabilisation with and without hydroxyapatite (HA) coating of the pedicle screws.

From our series of 570 Dynesys procedures, we studied patients with HA coated screws with a minimum one year follow-up.

Patients were entered prospectively and followed up at 6 weeks, 3, 6, and 12 months and annually thereafter. Plain radiographs were obtained annually. 58 patients (26 males, 32 females, mean age 55 years at surgery) underwent Dynesys stabilisation with HA coated screws. The data was compared with 69 patients who underwent Dynesys stabilisation with non-coated pedicle screws between 2004 and 2006 (26 male, 53 female, mean age 54 years). Outcome measures were screw loosening, breakage, implant removal or revision.

A total of 320 HA coated pedicle screws were inserted. 12 patients were lost to follow-up. 2 patients underwent subsequent level extension, and 2 had their implants removed. There were four screw breakages in three patients, all affecting S1 screws. There was no evidence of screw loosening in any patient. In the non-HA coated group 354 pedicle screws were inserted. 5 patients required revision or subsequent surgery. 12 patients had screw loosening and required implant removal. There was a significant improvement of anchorage of the HA coated screws.

Change to HA coating was investigated because of high loosening in plain screws. The improvement has been highly significant. Flexible stabilisation is a better model than fusion because the implant remains under constant load.

Disclosure: The authors did not receive any outside funding in support of preparation of this work.

Introduction

Hydroxyapatite (HA) coated femoral stems require a press fit for initial stability prior to osteointegration occurring. However this technique can lead to perioperative femoral fracture.

Introduction: Forward slip of the above vertebra may compromise the exit foramen and produce nerve root signs. Conservative management should be attempted first. However in 10–15% surgical procedures are required to control symptoms of backpain and radiculopathy.

In this cohort study, we compare the functional outcome of Dynesys in patients with degenerative spondylolisthesis categorised in three subgroups.

Material & Methods: Seventy eight patients with degenerative spondylolisthesis were treated with Dynesys. Patients were sub-grouped into Dynesys alone (group 1 n=31), Adjunct fusion (group 2 n=34) and Adjunct decompression (group 3 n=13). Three main outcome parameters were reviewed; ODI, VAS and the need for further surgeries. Patients follow up was arranged at 2 weeks, 3 months, 6 months, 12 months then annually.

Results: Average follow up was 53 months, 47 months & 55 months in groups 1, 2 & 3 respectively.

Patients with Dynesys alone had initial good improvement in ODI & VAS but this was not maintained. Secondary surgery was needed in 32% at 28.2 months.

Dynesys with adjunct PLIF showed clinically & statistically maintained ODI & VAS outcome. Secondary surgery rate was 11.7% at 26 months.

Dynesys with adjunct decompression group was favoured by clinically & statistically improved functional outcome. Second surgery was necessary in 7.6%.

Discussion: Dynesys stands as an innovative device for the treatment of backpain. However, its clinical indications were not refined. Patients with degenerative spondylolisthesis require decompression with instrumented stabilisation.

Conclusion: Dynesys alone is not recommended for degenerative spondylolisthesis.

Conflicts of Interest: None

Source of Funding: Zimmer Spine sponsored research fellowship at the Conquest hospital between 2005–2007. The funds were paid direct to the hospital for follow up and maintenance of Dynesys database. No researcher received direct fund by the company.

The medium term results of the JRI Furlong Total hip replacement have been very impressive to date. We report the longest prospective series to date of a hydroxyapatite coated femoral prosthesis (Joint Replacement Instrumentation limited, London, UK) at 15–21 years follow up. We describe the long term clinical and radiological femoral stem survival of 331 consecutive JRI Furlong Hydroxyapatite coated total hip replacements in 291 patients at an average follow-up of 17.5 years (15 – 21 year). Two patients (0.6%) were lost to follow-up over the 21 years of the study period. Using revision of the femoral stem for any reason as an endpoint, we report a stem survival of 97.4 % (81.0 to 99.5). Using Aseptic loosening as an endpoint, stem survival was 100%.

The average Merle, D’Aubine & Postel scores recorded for the patients was 5.63/6 for Pain, 5.42/6 for mobility and 4.50/6 for function. There were no cases of anterior thigh pain relating to the uncemented femoral stem.

These results compare favourably with the best long term survival of cemented or uncemented femoral stems used in total hip replacements.

Introduction: In this study we have studied the range of motion within Dynesys treated discs and levels adjacent to flexible stabilisation.

Dynesys was designed to offer physiological motion at the lumbar spine. An advantage which is superior to abolishing movements through spinal fusion.

Methods: A cohort of 75 post-Dynesys patients had weight-bearing lateral lumbar spine x rays in flexion/extension positions. Evaluation was done through PACS™ digital software. Flexibility at individual disc level was measured as the differences between flexion/extension angles accurate to within 1°. Motion was evaluated at the index and immediate adjacent levels.

Results: Patients with single level Dynesys had an average ROM of (3+/−4.7) at L5-S1 and (5.1+/−2.9) at the immediate adjacent level. Two levels Dynesys was associated with a ROM of 5+/−3.6 at L5-S1 & L4–5 and 3.5+/−1.8 at their immediate neighbour disc. Across three levels, Dynesys favoured a ROM of 5.3+/−2.5 at the operated sites and 1.6+/− 2 at the adjacent level.

Discussion & Conclusion: This study is the first radiological research to confirm the flexibility of Dynesys. Controlled motion at the dynesys treated disc levels share to distribute global spinal movements. This will advantage the next disc segments and protects them from risk of developing “accelerated adjacent segment disease”.

Introduction: In this study we report our experience with the clinical outcomes following Dynesys. Our objectives are to revalidate the most suitable indication(s) of Dyne-sys in patients with backpain.

Method: A prospective cohort study on 374 consecutive patients who had Dynesys for backpain from September 2000 to-present. Average age of patients was 57 years and male to female ratio were (40%:60%). Preoperative assessment involved ODI, SF36, VAS for leg and backpain and the diagnosis was confirmed with physical examination, x rays, spinal probe and lumbar spine MRI. Regular follow up was arranged at 2 weeks, 3, 6 and 12 months then on annual intervals.

In our cohort, clinical indications were:

t-test was used for comparison between preoperative and postoperative scores and p-value was used to show the significance.

Results: Overall outcome assessment revealed significant improvement in ODI, SF36 and VAS in comparison with preoperative status (p-value < 0.05). Improvement was greatest in DDD group and average for ASD.

Patients with stenosis performed better when the procedure involved adjunct decompression. Similarly, results of decompression and fusion were better than Dynesys alone in patients with spondylolisthesis.

Discussion and Conclusion:

Dynesys was successfully controlled symptoms of DDD in the intermediate term.

Introduction: In this study we describe Modic changes within treated-lumbar disc levels and levels adjacent-to-Dynamic Neutralisation System for the Spine (Dynesys).

Modic changes(M) have been described in association to Degenerative Disc Disease(DDD). Type-I represents the inflammatory phase whereas Type-II describes fatty changes within the vertebral marrow and endplate. Type-III is more advanced degeneration and it indicates marked sclerosis adjacent to endplates.

Material & Methods: Postoperative MRI has been compared to preoperative scan in 28 symptomatic patients treated with Dynesys. Parameters assessed were Modic changes within treated disc levels and their adjacent segments. Average time to postoperative MRI was 36 months with a range of 17–66 months.

Results: Within Dynesys-treated levels; 16 levels had no Modic change preoperatively of which 13 remained unchanged while 3 developed M2 with treatment. 15 had M2, of which, 7 worsen to M3, 6 continued as M2 and 2 improved to M0. 12 had M3, of which 1 improved to M1 and the rest did not change.

Adjacent endplate levels showed worsening of M0 to M2 in 11 patients while no change was seen in 35 levels. Only 4 levels with M2 were seen, of which 3 levels did not change and 1 level continued to M3. 2 M3 improved to M2.

Discussion & Conclusion: Compared to recently published studies by Danish group, Modic changes have the tendancy to worsen on conservative treatment. In this study we could show that following Dynesys progress of Modic changes at the treated level(s) was not remarkable though few cases continued with the process of degeneration.

Introduction: In this study, we report interobserver reliability of X-ray for the interpretation of pedicle screw osteointegration based on the diagnosis of “Halo zone” surrounding the screw.

Dynamic stabilisation system for the spine relies on titanium screw purchase within the pedicle. Decision on osteointegration is important especially when the patient becomes symptomatic following initial good outcome. From our cohort of 420 Dynesys patients, over all incidence of screw loosening was 17%. Only 35% were symptomatic.

Method: Lumbar spine X-ray images of 50 patients in two views (AP and lateral) randomly selected from our cohort of 420 Dynesys patients. The images were deployed in a CD-ROM. The authors were asked to review the images and state whether or not each pedicle screw is loose (total of 258 pedicle screws).

Seven observers composed of two expert orthopaedic spine consultant surgeons and one spine expert consultant radiologist and four Specialist Registrars in orthopaedics and radiology.

Data gathered were distributed and presented in tables in the form of descriptive statistics. The evaluation of interobserver agreement was performed by obtaining a Kappa (K) index. For continuous variables comparison, the t test was employed, with a significance level of 0.05.

Results: Kappa Index among three experts was 0.2198 at 95% CI (−0.0520, 0.4916) while for all 7 assessors (3 Experts & 4 SpR), KI was 0.1462 at 95% CI (0.0332, 0.2592)

Discussion & Conclusion: Kappa Index among expert assessors was 0.2 which means X-ray is unreliable for the assessment of pedicle screw osteointegration. Validity of X-ray is not applicable as it is unreliable.

We are planning to evaluate a 3D computer reconstruction model based on 2 X-ray views at 45 degree angle to each other which might be sensitive to detect screw loosening.

Introduction: In this study, we report interobserver reliability of X-ray for the interpretation of pedicle screw osteointegration based on the diagnosis of “Halo zone” surrounding the screw.

Dynamic stabilisation system for the spine relies on titanium screw purchase within the pedicle. Decision on osteointegration is important especially when the patient becomes symptomatic following initial good outcome. From our cohort of 420 Dynesys patients, over all incidence of screw loosening was 17%. Only 35% were symptomatic.

Method: Lumbar spine X-ray images of 50 patients in two views (AP and lateral) randomly selected from our cohort of 420 Dynesys patients. The images were deployed in a CD-ROM. The authors were asked to review the images and state whether or not each pedicle screw is loose (total of 258 pedicle screws).

Seven observers composed of two expert orthopaedic spine consultant surgeons and one spine expert consultant radiologist and four Specialist Registrars in orthopaedics and radiology.

Data gathered were distributed and presented in tables in the form of descriptive statistics. The evaluation of interobserver agreement was performed by obtaining a Kappa (K) index. For continuous variables comparison, the t test was employed, with a significance level of 0.05.

Results: Kappa Index among three experts was 0.2198 at 95% CI (−0.0520, 0.4916) while for all 7 assessors (3 Experts & 4 SpR), KI was 0.1462 at 95% CI (0.0332, 0.2592)

Discussion & Conclusion: Kappa Index among expert assessors was 0.2 which means X-ray is unreliable for the assessment of pedicle screw osteointegration. Validity of X-ray is not applicable as it is unreliable.

We are planning to evaluate a 3D computer reconstruction model based on 2 X-ray views at 45 degree angle to each other which might be sensitive to detect screw loosening.

Introduction: We report a series of 10 cases from a cohort of 421 Dynesys procedures in which evidence of Accelerated Adjacent Disc Disease (AASDD).

Spinal fusion for degenerative disc disease is known to have inconsistent outcomes. One concern is the possibility of AASDD as a result of the altered kinematics. The Dynamic Neutralisation System (Dynesys) appears to offer an advantage in that it restricts, rather than abolishes movement at the treated segment, and should thereby reduce the problem of AASDD, In the event of failure, it can in addition be removed, returning the spine to the former status quo. Various biomechanical studies confirmed flexibility of Dynesys.

Method: Ten patients developed new and symptomatic disc disease within segments adjacent to Dynesys. The average age of patients was 49 year with range between 36–70 years. Average post Dynesys to secondary surgery for ASD was 24.7 months. Previous discography and MRI in all cases had shown no evidence of disc disease within these adjacent segements prior to Dynesys. All patients were evaluated preoperatively using Oswestry Disability Index, SF 36 and Visual Analogue Scores together with plain x ray imaging, MRI scanning and discography. Of this cohort Dynesys was indicated to treat single disc level in 7 and two levels in 3

Results: Incidence of AASDD associated with Dynesys was 2.1%. Further surgical intervention included:

Extension of Dynesys10

There was no caudal ASD in our cohort.

Discussion & Conclusions: Dyensys did not prevent the development of accelerated ASD. Evidence from Aylott cadaver studies suggests that Dynesys instrumentation alters the Kinematics of the adjacent segment and increases the excursion. It is unclear whether the small number of AASDD reported here is other than the natural progression of degenerative change. 95.7 cases did not progress.

Introduction: The results of the FDA trial for Dynesys stabilisation implied that the procedure was effective as a method of treatment for this condition. However, all the American cases had adjunct decompressive treatment. In this study we report the outcome of the first two years following DYNESYS for Spondylolisthesis in two groups of patients; Dynesys alone and Dynesys with fusion.

Method: Fifty five patients had Dynesys for symptomatic Spondylolisthesis which was indicated for surgical treatment. Average age for group 1 was 51 years with range of 36–85 years whereas in group 2, average age was 59 years with range of 31–79 years. Patients were evaluated preoperatively using ODI, SF36, VAS, plain x-ray, MRI scanning & discography. 33 of the patients underwent Dynesys alone (group 1) while 22 underwent dynesys with fusion (group 2). Previous decompression surgery was noted in 10 in group 1 and 8 in group 2.

Results: In the first year following Dynesys, both groups did show significant improvement in all the four parameters; VAS (back and leg), ODI and SF36. In group 2 slight deterioration was noted in year 2 and while group 1 continued to improve, Subsequently 3 group 1 patients underwent fusion and 12 required removal/revision of Dynesys (40%).

Discussion & Conclusions: Dynesys alone in the treatment of spondylolysthesis resulted in a 45% re-operation rate, and we believe it should not be recommended as an indication.

Introduction: We report the outcome two years following Dynesys for the treatment of Spinal Canal Stenosis. In both the FDA trial and the European multicentre study, stenosis was invariably combined with decompression, invalidating conclusions on the results of Dynesys alone.

Method: Eighteen patients had symptomatic Spinal Canal Stenosis with root claudication sufficient to justify surgical intervention. Average age of patients was 68 with a range between 44–86 years. Dynesys was applied for the treatment of a single level in 4, two levels in 8, and more than two levels in 6.

Patients were evaluated preoperatively using ODI, SF36, VAS, plain x-ray, MRI scanning & discography. Questionnaires were evaluated at the first and second years.

Results: 2 patients had undergone previous spinal decompression, and decompression at the time of Dynesys surgery in 7. In the remaining 9 cases, no decompression was used, relying on distraction alone as in the X stop system. In this latter group, stenotic symptoms failed to resolve. Removal of Dynesys was indicated in 3 (16.6%).

Discussion & Conclusions: Dynesys alone is not recommended as a treatment for symptomatic spinal stenosis. A separate study is required to address the question of whether Dynesys adjunct improves the back pain outcome compared with decompression alone.

Background: Spinal fusion for degenerative disc disease remains a controversial issue due to adjacent segment disease. Several alternatives have been evaluated; including Dynamic Neutralisation System for Spine and artificial disc arthroplasty. In our cohort study, we are highlighting advantages of DYNESYS over TDA and fusion as being a simple and reversible procedure if removal of implants is necessary.

Materials and Methods: Prospective cohort study on 415 patients underwent DYNESYS. The implant has to be removed in 43 patients. Patients were evaluated preoperatively using Oswestry Disability Index, SF 36 and Visual Analogue Scores together with plain imaging and MRI scanning. Preoperative discography was performed in 81% of patients. Questionnaires were evaluated on subsequent follow up at 3 & 6 months, 1 year then at annual intervals.

Results: Average treatment period was 26 months with a range from 3/12 to 60/12. The main reason for DYNE-SYS removal was screws’ failure or loosening followed by infections. The implant was used to treat single disc space in 20.9%, two spaces in 67.4% and three disc spaces in 9.3%. 81% of the screws were not Hydroxy-appetite coated. No loosening was detected among HA coated screws.

Outcome assessment revealed significant improvement in SF36 even after removal of stabilising system while no worsening of ODI or VAS in comparison with preoperative status.

Conclusions: DYNESYS can maintain disc height and restricts movements exceeding physiological limits. HA coated screws have superior biomechanical characteristics in preventing screw loosening and subsequent spinal spasms. If necessary, removal of implants is a simple procedure.

Background: Spinal fusion for degenerative disc disease remains a controversial issue due to adjacent segment disease. Several alternatives have been evaluated; including Dynamic Neutralisation System for Spine and artificial disc arthroplasty. In our cohort study, we are highlighting advantages of DYNESYS over TDA and fusion as being a simple and reversible procedure if removal of implants is necessary.

Material & Methods: Prospective cohort study on 415 patients underwent DYNESYS. The implant has to be removed in 43 patients. Patients were evaluated preoperatively using Oswestry Disability Index, SF 36 and Visual Analogue Scores together with plain imaging and MRI scanning. Preoperative discography was performed in 81% of patients. Questionnaires were evaluated on subsequent follow up at 3/12, 6/12 then at annual intervals.

Results: Average treatment period was 26 months with a range from 3/12 to 60/12. The main reason for DYNE-SYS removal was screws’ failure or loosening followed by infections. The implant was used to treat single disc space in 20.9%, two spaces in 67.4% and three disc spaces in 9.3%. 81% of the screws were not Hydroxy Appetite coated. No loosening was detected among HA coated screws.

Outcome assessment revealed significant improvement in SF36 even after removal of stabilising system while no worsening of ODI or VAS in comparison with preoperative status.

Conclusions: DYNESYS can maintain disc height and restricts movements exceeding physiological limits. HA coated screws have superior biomechanical characteristics in preventing screw loosening and subsequent spinal spasms. If necessary, removal of implants is a simple procedure.