Motion Preservation Surgery Research Articles

Progressive First Metatarsal Shortening Is Observed Following Allograft Interpositional Arthroplasty in Hallux Rigidus

Introduction/Purpose: Interpositional arthroplasty (IPA) is a motion-preserving surgery in patients with advanced hallux rigidus. Literature displays several complications after the procedure including transfer metatarsalgia, cock-updeformity and infection. In a finite element model, shortening of the first metatarsal was associated with increased plantar pressure on lateral rays during gait. Additionally, there are reports of a positive correlation between first metatarsal shortening after hallux valgus surgery and transfer metatarsalgia of the second,third and fourth metatarsophalangeal joints. The goals of this study were to report the outcomes and complications of IPA using acellular dermal allograft (IPA-ADA) as well as study the changes in the length of the proximal phalanx of the hallux (P1) and the first metatarsal (M1) following the procedure. Methods: In this IRB-approved retrospective study, we assessed patients who underwent IPA-ADA in a single academic institute from 2019-2022. All patients’ demographic data, surgical details, complications, and patient-reported outcomes (PROs) were extracted. On standing conventional anteroposterior (AP) foot views, we measured the lengths of the first metatarsal (M1), the second metatarsal (M2), the proximal phalanx of the big toe (P1), and the entire length of the hallux (HX). The ratio of M1/M2 and P1/HX were calculated. The first metatarsophalangeal joint space was measured at the medial and lateral aspects of the joint on the APview. All measurements were recorded pre-operatively, at six weeks follow-up, and at the final follow-up. Descriptive statistics were performed, and comparison between groups was performed using analysis of variance(ANOVA) or Kruskal Wallis test according to data normality. The Dunn-Bonferroni test was then performed for pairwise group comparisons. A p-value < 0.05 was considered significant. Results: Eleven patients were included, 9 being females (81.81%). Six were hallux rigidus Coughlin grade III (54.55%), and 5 were grade IV (45.45%). The average age was 59 years (SD±6.78), and the body mass index (BMI) was 26 (SD±4.79). At the final follow- up, there was significant shortening of the first ray in comparison to the pre-operative length evidenced by lower M1/M2 (82.63 SD±2.29 versus 75.42 SD±5.1; p=0.001) and P1/HX ratio53.38 ± 2.29 versus 48.98 SD ± 7.92; p=0.001). Although there was no significant difference between M1/M2 at 6 weeks and at the final follow-up (p=0.716), there was a significant negative correlation between follow-up length and M1/M2 (r= -0.76, p=0.003). Follow-up was (19.95 months; range 3-39). Complications and PROs are listed in Figure 1. Conclusion: Interposition arthroplasty using dermal allograft for HR is associated with progressive shortening of the first ray at the level of the first metatarsal as well as the proximal phalanx. Although the study did show shortening of the first ray, the small sample size didn't allow for a correlation between this shortening and complications such as transfer metatarsalgia and cock-up toe deformity. The potential shortening should be considered in the selection of patients, particularly in the setting of an already short first metatarsal or when simultaneous Akin/Moberg osteotomy is planned. Interposition arthroplasty using dermal allograft for HR is associated with progressive shortening of the first ray at the level of the first metatarsal as well as the proximal phalanx. Although the study did show shortening of the first ray, the small sample size didn't allow for a correlation between this shortening and complications such as transfer metatarsalgia and cock-up toe deformity. The potential shortening should be considered in the selection of patients, particularly in the setting of an already short first metatarsal or when simultaneous Akin/Moberg osteotomy is planned.

279 Does Surgical Treatment of Lumbar Spondylolisthesis Impact Self-care and Functional Independence? Five-Year Analysis of the Quality Outcomes Database

INTRODUCTION: Lumbar spondylolisthesis may have an impact on patients’ ability to care for oneself and maintain functional independence. Surgical treatment is associated with improvement in patient function but the impact on self-care is not well understood. METHODS: This is a retrospective analysis of the multicenter, prospectively collected Quality Outcomes Database (QOD). Patients with surgically treated grade I lumbar spondylolisthesis with five years of follow-up were included. Patient reported outcomes (PROs) were recorded. Patients were grouped into baseline dependent or independent cohorts based on the Personal Care component of the ODI (0-2=independent; ³3=dependent). Minimum clinically important difference (MCID) was defined as a 30% reduction from baseline disability. RESULTS: Of the 602 patients, 535 (89%) were independent and 67 (11%) were dependent at baseline with mean age of 63 and 59, respectively (p = 0.01). 479 patients (80%) reported 60-month follow up Personal Care scores, with 59% reporting improvement and 41% having worse or no improvement. At 60-month follow-up, 87.5% of dependent patients had gained lasting independence. Dependent and independent cohorts met 5-year MCIDs at similar rates. Baseline dependence was universally associated with worse pre-operative PROs (p < 0.01). 60-month improvement in personal care was associated with greater satisfaction and rates of MCID for all PROs (p < 0.01). 60-month improvement in personal care was positively associated with surgical treatment including arthrodesis versus motion-preserving surgery (OR = 1.17, 95%CI 1.04-1.32, p = 0.01). CONCLUSIONS: Dependent patients with lumbar spondylolisthesis achieve very high rates of independence (87.5%) which is durable through 5 years of follow-up. The dependent cohort represented only 11% of the cohort and was significantly younger at baseline. Spondylolisthesis patients treated with arthrodesis are more likely to improve their long-term self-care and independence.

Progressive First Metatarsal Shortening is Observed Following Allograft Interpositional Arthroplasty in Hallux Rigidus

Category: Midfoot/Forefoot; Bunion Introduction/Purpose: Interpositional arthroplasty (IPA) is a motion-preserving surgery in patients with advanced hallux rigidus. Literature displays several complications after the procedure including transfer metatarsalgia, cock-up deformity and infection. In a finite element model, shortening of the first metatarsal was associated with increased plantar pressure on lateral rays during gait. Additionally, there are reports of a positive correlation between first metatarsal shortening after hallux valgus surgery and transfer metatarsalgia of the second, third and fourth metatarsophalangeal joints. The goals of this study were to report the outcomes and complications of IPA using acellular dermal allograft (IPA-ADA) as well as study the changes in the length of the proximal phalanx of the hallux (P1) and the first metatarsal (M1) following the procedure. Methods: In this IRB-approved retrospective study, we assessed patients who underwent IPA-ADA in a single academic institute during the period 2019-2022. All patients’ demographic data, surgical details, complications, and patient-reported outcomes (PROs) were extracted. On standing conventional anteroposterior (AP) foot views, we measured the lengths of the first metatarsal (M1), the second metatarsal (M2), the proximal phalanx of the big toe (P1) and the entire length of the hallux (HX). The ratio of M1/M2 and P1/HX were calculated. The first metatarsophalangeal joint space was measured at the medial and lateral aspects of the joint on the AP view. All measurements were recorded pre-operatively, at six weeks follow-up and at the final follow-up. Descriptive statistics were performed, comparison between groups was performed using analysis of variance (ANOVA) or Kruskal Wallis test according to data normality. The Dunn-Bonferroni test was then performed for pairwise group comparisons.A p-value < 0.05 was considered significant. Results: Eleven patients were included, 9 being females (81.81%). Six were hallux rigidus Coughlin grade III (54.55%) and 5 were grade IV (45.45%). The average age was 59 years (SD±6.78) and the body mass index (BMI) was 26 (SD±4.79). At the final follow- up, there was significant shortening of the first ray in comparison to the pre-operative length evidenced by lower M1/M2 (82.63 SD±2.29 versus 75.42 SD±5.1; p=0.001) and P1/HX ratio 53.38 ± 2.29 versus 48.98 SD ± 7.92; p=0.001). Although there was no significant difference between M1/M2 at 6 weeks and at the final follow-up (p=0.716), there was a significant negative correlation between follow-up length and M1/M2 (r= -0.76, p=0.003). Follow-up was (19.95 months; range 3-39). Complications and PROs are listed in Figure 1. Conclusion: Interposition arthroplasty using dermal allograft for HR is associated with progressive shortening of the first ray at the level of the first metatarsal as well as the proximal phalanx. Although the study did show shortening of the first ray, the small sample size didn't allow for a correlation between this shortening and complications such as transfer metatarsalgia and cock-up toe deformity. The potential shortening should be considered in the selection of patients, particularly in the setting of an already short first metatarsal or when simultaneous Akin/Moberg osteotomy is planned.

Are We Looking at a Paradigm Shift in the Management of Adolescent Idiopathic Scoliosis? Comprehensive Retrospective Analysis of 75 Patients of Nonfusion Anterior Scoliosis Correction with 2-5-Year Follow-up: A Single Center Experience.

Retrospective cohort study. This study aimed to evaluate the clinical and radiological outcomes of nonfusion anterior scoliosis correction (NFASC) in patients with idiopathic scoliosis and comprehensively analyze its principles. NFASC is a novel revolutionary motion-preserving surgery for idiopathic scoliosis. However, clinical data related to this procedure remain scarce, with no conclusive guidelines regarding case indications, proper technique, and possible complications. This study included patients with adolescent idiopathic scoliosis (AIS) who were treated with NFASC for a structural major curve (Cobb angle, 40°-80°) with more than 50% flexibility on dynamic X-rays. The mean follow-up was 26±12.2 months (range, 12- 60 months). Clinical and radiological data such as skeletal maturity, curve type, Cobb angle, surgery details, and Scoliosis Research Society-22 revised (SRS-22r) questionnaire were collected. Statistically significant trends were examined by post hoc analysis following repeated measures analysis of variance test. A total of 75 patients (70 females, five males) were included, with a mean age of 14.96±2.69 years. The mean Risser and Sanders scores were 4.22±0.7 and 7.15±0.74, respectively. The mean main thoracic Cobb angles at the first and second follow-up (17.2°±5.36° and 16.92°±5.06°, respectively) were significantly lower than the preoperative Cobb angles (52.11°±7.74°) (p <0.05). Similarly, the mean thoracolumbar/lumbar Cobb angle significantly improved from the preoperative period (51.45°±11.26°) to the first follow-up (13.48°±5.11°) and last follow-up (14.24°±4.85°) (p <0.05). The mean preoperative and postoperative SRS-22r scores were 78.0±3.2 and 92.5±3.1, respectively (p <0.05). None of the patients had any complications until the most recent follow-up. NFASC offers promising curve correction and curve progression stabilization in patients with AIS, with a low risk for complications and preservation of spinal mobility and sagittal parameters. Thus, it proves to be a favorable alternative to fusion modality.

Adjacent Segment Disease

Spinal fusion is gold-standard treatment for degenerative disc disease (DDD) both at cervical and lumbar spine, and it is time tested. Perhaps it has its bundle of complications. Elimination of motion results in accentuated degeneration of adjacent segments leading to adjacent segment degeneration radiographically and, if symptomatic, leads to adjacent segment disease. There is still a debate on whether there is such an entity or whether it is a manifestation of natural history or an iatrogenic phenomenon. Motion preservation surgeries were developed to address the same issue, which includes total disc replacement, nucleus replacement, interspinous implants, and dynamic posterior stabilization systems. The primary goal of motion preservation surgery is to maintain normal or near-normal motion in an attempt to prevent adverse outcomes, which are commonly seen with conventional spinal fusion, most notably the development of adjacent-level DDD. A search was conducted in PubMed using the terms (“adjacent segment”) AND (“disease” OR “degeneration” or “pathology”). Then the articles were shortlisted based on time of publication (2005 onward), publication in English and inclusion of human subjects. This resulted in 253 articles. Another search for ((“Motion preservation”) AND (“Spine”)) OR (“Adjacent segment disease”) OR (“Adjacent segment pathology”) OR (“Adjacent segment degeneration”) yielded 76 articles. This narrative review discusses various issues pertaining to the current evidence regarding adjacent segment disease (ASD), including the controversy on whether ASD is actually an entity, its etiopathogenesis, clinical features, as well as the role of motion preservation technologies to reduce its incidence. There is still enthusiasm and concerns regarding the benefits of motion preservation surgery since it is still an area of ongoing research.

MRI changes of adjacent segments after transforaminal lumbar interbody fusion (TLIF) and foraminal endoscopy: A case-control study.

Background:Intervertebral foramen endoscopy has developed rapidly, but compared with transforaminal lumbar interbody fusion (TLIF), the progress of degeneration is unknown. We aim to compare the changes of intervertebral disc and intervertebral foramen in adjacent segments after TLIF and endoscopic discectomy for patients with lumbar disc herniation (LDH).Methods:From 2014 to 2017, 87 patients who were diagnosed with single-level LDH and received surgery of TLIF (group T, n = 43) or endoscopic discectomy (group F, n = 44) were retrospectively analyzed. X-ray, MRI, CT and clinical symptoms were recorded before operation and at the last follow-up (FU). The neurological function was originally evaluated by the Japanese Orthopaedic Association (JOA) scores. Radiological evaluation included the height of intervertebral space (HIS), intervertebral foramen height (FH), intervertebral foramen area (FA), lumbar lordosis (CA) and intervertebral disc degeneration Pfirrmann scores.Results:There was no significant difference in baseline characteristics, JOA improvement rate, reoperation rate and complications between the two groups. The age, average blood loss, average hospital stays and average operation time in group F were lower than those in group T. During the last FU, HIS, CA and FA decreased in both groups, and the changes in group T were more significant than those in group F (P < .05). There was no significant difference in FH changes between the two groups (P > .05).Conclusion:Both TLIF and endoscopic surgery can achieve good results in the treatment of LDH, but the risk of lumbar disc height loss and intervertebral foramina reduction in the adjacent segment after endoscopic surgery is lower.

What's New in Spine Surgery.

What's New in Spine Surgery.

Motion preservation surgery for scoliosis with a vertebral body tethering system: a biomechanical study

PurposeThere is a paucity of studies on new vertebral body tethering (VBT) surgical constructs especially regarding their potentially motion-preserving ability. This study analyses their effects on the ROM of the spine.MethodsHuman spines (T10-L3) were tested under pure moment in four different conditions: (1) native, (2) instrumented with one tether continuously connected in all vertebrae from T10 to L3, (3) additional instrumented with a second tether continuously connected in all vertebrae from T11 to L3, and (4) instrumented with one tether and one titanium rod (hybrid) attached to T12, L1 and L2. The instrumentation was inserted in the left lateral side. The intersegmental ROM was evaluated using a magnetic tracking system, and the medians were analysed.Please check and confirm the author names and initials are correct. Also, kindly confirm the details in the metadata are correct. The mentioned information is correctResultsCompared to the native spine, the instrumented spine presented a reduction of less than 13% in global ROM considering flexion–extension and axial rotation. For left lateral bending, the median global ROM of the native spine (100%) significantly reduced to 74.6%, 66.4%, and 68.1% after testing one tether, two tethers and the hybrid construction, respectively. In these cases, the L1-L2 ROM was reduced to 68.3%, 58.5%, and 38.3%, respectively. In right lateral bending, the normalized global ROM of the spine with one tether, two tethers and the hybrid construction was 58.9%, 54.0%, and 56.6%, respectively. Considering the same order, the normalized L1-L2 ROM was 64.3%, 49.9%, and 35.3%, respectively.ConclusionThe investigated VBT techniques preserved global ROM of the spine in flexion–extension and axial rotation while reduced the ROM in lateral bending.

Relationship between ankle varus moment during gait and radiographic measurements in patients with medial ankle osteoarthritis.

Kinetic data obtained during gait can be used to clarify the biomechanical pathogenesis of osteoarthritis of the lower extremity. This study aimed to investigate the difference in ankle varus moment between the varus angulation and medial translation types of medial ankle osteoarthritis, and to identify the radiographic measurements associated with ankle varus moment. Twenty-four consecutive patients [mean age 65.8 (SD) 8.0 years; 9 men and 15 women] with medial ankle osteoarthritis were included. Fourteen and 10 patients had the varus angulation (tibiotalar tilt angle≥3 degrees) and medial translation (tibiotalar tilt angle<3 degrees) types, respectively. All patients underwent three-dimensional gait analysis, and the maximum varus moment of the ankle was recorded. Radiographic measurement included tibial plafond inclination, tibiotalar tilt angle, talar dome inclination, and lateral talo-first metatarsal angle. Comparison between the two types of medial ankle osteoarthritis and the relationship between the maximum ankle varus moment and radiographic measurements were analyzed. The mean tibial plafond inclination, tibiotalar tilt angle, talar dome inclination, lateral talo-first metatarsal angle, and maximum ankle varus moment were 6.4 degrees (SD 3.3 degrees), 5.0 degrees (SD 4.6 degrees), 11.4 degrees (SD 5.2 degrees), -6.5 degrees (SD 11.7 degrees), and 0.185 (SD 0.082) Nm/kg, respectively. The varus angulation type showed a greater maximum ankle varus moment than the medial translation type (p = .005). The lateral talo-first metatarsal angle was significantly associated with the maximum ankle varus moment (p = .041) in the multiple regression analysis. The varus angulation type of medial ankle osteoarthritis is considered to be more imbalanced biomechanically than the medial displacement type. The lateral talo-first metatarsal angle, being significantly associated with the ankle varus moment, should be considered for correction during motion-preserving surgeries for medial ankle osteoarthritis to restore the biomechanical balance of the ankle.

Outcomes and technical issues of transcorporeal anterior cervical microforaminotomy in patients with cervical brachialgia

IntroductionTranscorporeal anterior cervical microforaminotomy is a motion-preserving surgery. It addresses directly to the prolapsed disc in contrast to posterior laminoforaminotomy and does not affect facet joints; in the transuncal approach, there is a chance of vertebral artery injury and it also decreases disc height; hence, may alter the motion of that segment. ObjectiveAim is to assess the outcome of surgery and its effectiveness. MethodsA total of 40 patients were observed retrospectively of which 33 were male and 7 were female. A single study of transcorporeal anterior cervical microforaminotomy was analyzed in a private hospital (Comfort Hospital), Dhaka, Bangladesh. Patients having pure brachialgia who were not relieved by conservative treatment over 6–8 weeks in cervical disc prolapse were included in the study. Patients having more than one level of disease, features of myelopathy, or instability were excluded from the study. ResultsAll patients were pain-free postoperatively, although after one to two months 2 out of 40 patients developed brachialgia and required anterior cervical discectomy and fusion. ConclusionTranscorporeal microforaminotomy for brachialgia is a safe and effective approach that is motion preserving and minimally invasive as well.

Results after treatment of congenital radioulnar synostosis: a systematic review and pooled data analysis.

Congenital radioulnar synostosis (CRUS) is one of the most common congenital disorders affecting the elbow and forearm, with the forearm being fixed in a range of positions usually varying from neutral rotation to severe pronation. The aim of this study, apart from a systematic review of all surgical procedures described for CRUS, is to derive any correlation between various influencing factors, outcomes and complications. This review was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses format by an electronic literature search of Ovid, MEDLINE and the Cochrane Library databases. Grading was according to the Newcastle-Ottawa scale and the Modified Coleman Methodology Score. Demographic data, surgical procedures, outcomes and complications were analyzed. Outcome data were pooled to establish means and ranges across all studies. Spearman correlations were performed. A total of 23 articles, showing a poor overall study quality (all Level of Evidence IV), met the inclusion criteria. A total of 374 forearms with a mean age of 6.7 years (2.0–18.8) were analyzed. Derotational surgeries were more commonly performed (91%) than motion-preserving surgeries (9%). The mean deformity improved from 64.8° pronation (−75° to 110°) to a mean of 2.8° pronation (−50° to 80°). In total, 17.9% of patients presented with complications. A significant correlation was noted between age and major complications, proximal osteotomies and complications, and postoperative loss of reduction and double level osteotomies as the primary treatment modality. Most of the complications occurred above the threshold of 65–70° of correction and in children 7 years and above. Surgery is essential to improve the quality of life of children with CRUS. However, each type of surgery is associated with complications, along with the respective hardware being used in rotation osteotomies. Caution is, nevertheless, warranted in interpreting these results in view of the inherent limitations of the included studies.

Clinico-Radiological Outcome of Single-Level and Hybrid Total Disc Replacement with Spineart Baguera®-C for Cervical Myeloradiculopathy: Minimum 2-Year Follow-Up Study in Indian Population.

Context:Cervical radiculopathy and myelopathy is one of the most frequent ailments encountered by spine surgeon. Motion-preserving surgeries in cervical spine is a standard of care due to its certain advantages such as biomechanical anatomical conformity, reduced chances of adjacent segment degeneration, and revision surgeries. While there is abundant data from some centers, data from developing countries are still limited.Aims:The aim was to study the clinico-radiological outcome of single-level and hybrid total disc replacement (TDR) with Spineart Baguera®-C cervical prosthesis for cervical myeloradiculopathy.Settings and Design:Retrospective study.Materials and Methods:Retrospective analysis of the 29 consecutive patient undergoing single level TDR and hybrid fixation (i.e., TDR with anterior cervical discectomy and fusion) with Spineart Baguera®-C cervical prosthesis for myeloradiculopathy from January 1, 2014 to December 31, 2017, was done. Radiological features and outcome were studied from data collected on Insta-picture archiving and communication system.Statistical Analysis Used:SAS 9.4 was used for all computations. Results on continuous measurements were presented as mean and standard deviation (min-max) and results on categorical measurements were presented as numbers (n) and percentages.Results:Twenty-nine patients were included in the study. The mean age was 43.31 ± 9.04 years with 14 males and 15 females. The most common level of TDR was C5-C6 (72.41%). The mean follow-up duration was 3.14 years ± 1.13 years (2–5 years). The mean hospital stay was 4.93 ± 2.12 days. The mean neck disability index (NDI) at admission was 27.24 ± 7.66 which decreased to 6.41 ± 4.29 at final follow-up.Conclusions:Two-year data on treatment with Spineart Baguera®-C cervical prosthesis shows significantly improved NDI, visual analog scale (arm) with maintenance of movement of the prosthesis.

A new concept of motion preservation surgery of the cervical spine: PEEK rods for the posterior cervical region.

Laminectomy may cause kyphotic postoperative deformity in the cervical region leading to segmental instability over time. Laminoplasty may be an alternative procedure to laminectomy, as it protects the spine against post-laminectomy kyphosis; however, similar to laminectomy, laminoplasty may cause sagittal plane deformities by destructing or weakening the dorsal tension band. Using finite element analysis (FE), we attempted to determine whether a posterior motion preservation system (PEEK posterior rod system concept) could overcome the postoperative complications of laminectomy and laminoplasty and eliminate the side effects of rigid posterior stabilization in the cervical region. We compared PEEK rods in four different diameters with a titanium rod for posterior cervical fixation. The present study may lead to motion preservation systems of the cervical vertebra. When PEEK rod is compared with titanium rod, considerable increase in range of motion is observed. PEEK rod-lateral mass screw instrumentation systems may be useful in motion preservation surgery of the posterior cervical region.

Cervical rotation before and after hinge-door cervical laminoplasty for cervical spondylotic myelopathy.

Background:Hinge-Door Cervical laminoplasty is commonly performed procedure in patients with cervical spondylotic myelopathy. Most available studies have established restriction of flexion and extension motion post laminoplasty but the literature on post-laminoplasty axial rotation is sparse.Objective:To study the axial neck rotation on either side following hinge door cervical laminoplasty.Materials and Methods:Twenty consecutive patients of cervical spondylotic myelopathy planned for cervical laminoplasty were included in the study. Preoperative and postoperative radiological data was recorded for each patient and analysed by an experienced neuroradiologist. The clinical and radiological follow-up was recorded at 6 months post surgery. All patients underwent standard hinge door C3-C6 laminoplasty preserving the muscle attachments to C2 and C7 vertebra.Results:There were 13 men and 7 women with a mean age of 60.5 years, age range 58-70 years. The mean preop C1 C2 rotation was 46.5 degrees and mean post-operative C1-C2 rotation was 44.3 degrees. The average subaxial cervical spine rotation was 11.66 degrees preoperatively and 12.47 degrees postoperatively. The global cervical spine rotation was 80.95 degrees preoperatively and 76.82 degrees postoperatively. There is no significant change in segmental, subaxial and global cervical spine rotation following hinge door C3-C6 laminoplasty preserving the muscle attachments to C2 and C7 vertebra.Conclusion:Cervical laminoplasty preserves cervical ROM and is a motion-preserving surgery as far as axial rotation is concerned.

Adjacent segment degeneration after fusion spinal surgery-a systematic review.

Adjacent segment degeneration (ASDeg) and disease (ASDis) have become major concerns after fusion surgery. However, there is no definitive data or knowledge about the incidence or risk factors. The review discusses the incidence and risk factors and prevention of ASDeg and ASDis in the relevant literature. We performed a systematic review of meta-analyses, randomized control trials, and cohort studies published in English to provide evidence-based information about ASDeg and ASDis. According to a meta-analysis, the pooled incidence of ASDeg after lumbar and cervical fusion surgery was 26.6% and 32.8%, respectively. Approximately 1/4-1/3 of ASDeg progressed to ASDis. Risk factors after cervical fusion surgery were young age, pre-existing disc degeneration, short fusion segment, high T1 slope, disruption of adjacent soft tissue, and plate placement close to the adjacent disc. The risk factors of ASDeg and ASDis after lumbar fusion surgery were age, genetic factors, high body mass index, pre-existing adjacent segment degeneration, laminectomy at the adjacent level of fusion, excessive distraction of the fusion level, insufficient lumbar lordosis, multilevel fixation, floating fusion, coronal wedging of L5-S disc, pelvic tilt, and osteoporosis. Motion-preserving surgeries seem to have less risk of ASDeg and ASDis than conventional fusion surgery both in the lumbar and cervical spine. The existent literature points out variables involved in ASDeg and ASDis. High evidence-level studies should provide more relevant data to guide strategies for avoiding ASDeg and ASDis.

Motion preservation surgery: excision of juxta C5-C6 intervertebral disc osteoid osteoma using 3D C-arm based navigation: technical report.

Introduction: Precise targeted excision of the C5–C6 osteoid osteoma with placement of reference array on clavicle with minimal disturbance of anatomy and motion.Methods: A 20-year-old male presented with an osteoid osteoma in the superior end plate of the C6 vertebra abutting the spinal canal causing intractable pain. The authors curetted the nidus using a 3D C-arm-based intraoperative scan integrated with an optical navigation system through a minimal access anterior cervical exposure. The patient reference array was affixed to the left clavicle using a threaded pin.Results: The postoperative CT-scan revealed complete excision. Follow-up MRI and CT after 12 months revealed C5–C6 intervertebral disc to be intact without evidence of any tumor recurrence. VAS for neck pain improved from 8/10 to 2/10 immediately postoperatively and 0/10 at 1 year follow-up with no limitation of cervical movement. A motion segment was preserved with this technique.Conclusions: Navigation allowed safe curettage of the nidus with minimal disturbance to the anatomy and motion. The site of attachment of patient reference array on clavicle can be recommended as stable, meeting all the criteria for optimal accuracy and stability.

Changes in cervical motion after cervical spinal motion preservation surgery.

For patients with single-level cervical radiculopathy, various types of motion preservation surgeries, such as total disc replacement (TDR), posterior cervical foraminotomy (PCF) and posterior percutaneous endoscopic foraminotomy and discectomy (PECF), are available. In addition to motion preservation, the quality of motion is an important issue. The aim of the present study was to evaluate the influence of these surgeries on cervical motion by comparing the instantaneous axis of rotation (IAR) among PECF, TDR and PCF at the index and superior/inferior adjacent segments. A retrospective review was performed of patients who underwent index surgery at C5-6 for cervical single-level foraminal disc herniation or foraminal stenosis. Patients with minimal degeneration at the index and other cervical spinal levels and flexion/extension cervical lateral radiographs both preoperatively and 6months postoperatively were included (PECF, 11 patients; TDR, 11 patients; PCF, 12 patients). The IARs were calculated at the index segment and segments above and below the index segment from the flexion and extension cervical lateral radiographs, which were obtained preoperatively and 6months postoperatively. A standardized cervical normogram was referenced to qualify shifts in the IAR. Postoperatively, neck pain was significantly decreased, with no difference among the surgical methods. The IARs were not significantly changed after the PECF. Although significant inferior shift occurred at C6-7 after TDR (p=0.02), the shift occurred within the normal range in the cervical normogram. However, significant inferior shifts in the IARs occurred after PCF at C5-6 (p=0.02) and C6-7 (p=0.02), and the IARs moved out of the normal range. The IARs were significantly changed after PCF at either the index segment or the adjacent segment below. The shifts in IAR at the index and adjacent segments were not significant after PECF and TDR. The sample size was too small to allow definitive conclusions, but the present study showed that PECF may be another alternative to motion preservation surgeries.

Spinal motion preservation surgery: indications and applications.

Fusion is one of the most commonly performed spinal procedures, indicated for a wide range of spinal problems. Elimination of motion though results in accelerated degeneration of the adjacent level, known as adjacent level disease. Motion preservation surgical methods were developed in order to overcome this complication. These methods include total disc replacement, laminoplasty, interspinous implants and dynamic posterior stabilization systems. The initial enthusiasm about these methods was followed by certain concerns about their clinical usefulness and their results. The main indications for total disc replacement are degenerative disc disease, but the numerous contraindications for this method make it difficult to find the right candidate. Application of interspinous implants has shown good results in patients with spinal stenosis, but a more precise definition is needed regarding the severity of spinal stenosis up to which these implants can be used. Laminoplasty has several advantages and less complications compared to fusion and laminectomy in patients with cervical myelopathy/radiculopathy. Dynamic posterior stabilization could replace conventional fusion in certain cases, but also in this case the results are successful only in mild to moderate cases.

Is Total Ankle Arthroplasty Justified in Stiff Ankles?

Category: Ankle Arthritis. Introduction/Purpose: Although recent studies have shown comparability of gait function following total ankle arthroplasty (TAA) and ankle arthrodesis, TAA is regarded to be functionally advantageous by preserving tibiotalar motion. However, it is unknown whether arthritic ankles with severe loss of sagittal plane motion are appropriate surgical candidates for arthroplasty. This study was undertaken to address the question: Is there a rationale for motion-preserving surgery in patients with little or no preoperative sagittal plane motion? Methods: A retrospective review of 76 patients who underwent isolated TAA with a minimum one-year follow-up, including patient demographics and pre and postoperative gait studies was conducted. Using a linear regression model, an effect size for total preoperative sagittal ROM was calculated, as well as effects of age, and patient demographics. Gait function was evaluated for postoperative improvement using multivariate analysis to determine the influence the variable on parameters of gait. P-values of &lt; 0.05 were considered statistically significant. Results: Outcomes/p-values are listed in table 1. Temporal Spatial Older patients had slower preoperative/postoperative walking speeds, and increased age resulted in diminished function. Increased preoperative ROM predicted greater preoperative and trended towards greater postoperative step length. Greater preoperative ROM predicted less total improvement. Kinematic Age was predictive of improved postoperative plantarflexion with negligible clinical significance. Preoperative ROM predicted greater postoperative ROM although less improvement was noted. Preoperative/postoperative sagittal angle at toe off was greater with increased preoperative ROM. No improvement was detected. Preoperative and postoperative plantarflexion/dorsiflexion were both greater with increased preoperative ROM. Less overall improvement in plantarflexion was noted with greater preoperative ROM. Kinetic Preoperative ROM was predictive of greater preoperative/postoperative ankle power. Greater preoperative ROM resulted in less improvement in power. Conclusion: Irrespective of preoperative total sagittal range of motion, there was a statistically and clinically significant improvement in function as measured by multiple, objective parameters of gait. While pre-operative range of motion was predictive of overall post-operative gait function, patients with greater pre-operative range of motion experienced less overall improvement in gait. The data show that TAA can offer statistically significant, and clinically meaningful improvement in gait function and is a reasonable treatment alternative even in patients with end-stage tibiotalar arthritis who have very limited preoperative sagittal range of motion.

Looking at the Future of Motion Preservation Surgery in the Lumbar Spine with the Experience of the Past

Introduction In the 1970's, Kirkaldy-Willis first described the “Degenerative Cascade” of DDD. Observation of demographic studies shows more back pain in younger adults (30 to 50 years) than in elderly adults (over 60 years) in which osteoarthritis problems are prevalent to disc problems. The aim of this study is to demonstrate if and when an interlaminar elastic motion preservation device for disc assistance can stop or reverse the degenerative cascade of the lumbar spine in younger adults. We used in this study a new motion preservation device not interspinous but interlaminar. The IntraSpine® device (Cousin Biotech, France), is manufactured in medical silicon 65 shore coated by an adherent pure polyester terephtalate sleeve and the frontal extremity is further covered by a silicone film that prevents adhesion to the neural structures in cases of surgical bone or soft tissue removal. Material and Methods Group 1: 60 patients (mean age 34.5 years, 38 female an 22 male) affected from back pain from a minimum time of two years and after the failure of conservative treatment for at least 6 months, received a minimally invasive surgical procedure implanting this IntraSPINE® device at one or two levels. Group 2: 54 patients (mean age 32,6 years, 24 male and 16 female) affected from big extruded disc hernia received the some implant after the removal of the hernia in the some surgical procedure at one level, to prevent the subsequent chronic LBP due to a rapid collapse of the disc height. From the literature we know that in this young group of patients the percentage of the chronic LBP in the late follow up (5 years) it's ~70%. The results with a minimum follow-up of 4 years were evaluated from the clinical point of view regarding the LBP with VAS and ODI tests. All patients were also subjected to an MRI control. The surgical procedure was performed by monolateral approach and in many cases in local anesthesia in group 1 and in general anesthesia and equally by monolateral approach in group 2. The source of the pain in this group of patients (facet joint pain) was demonstrated by a positive response to the facet joint block test (The response was considered positive for a transient reduction of pain at least of 70%). Prior to surgical procedure, all patients underwent an MRI, a CT Scan and a dynamic X-ray of the lumbar spine. The stage of the degenerative cascade was between grade III and IV according to Pfirrmann. Results Group 1:in ~20% also in presence of good clinical results we highlighted a moderate progression of the cascade, in about the 50% the Pfirrmann grade was unchanged, but in ~30% we highlighted a partial rehydration of the disc which means a initial reversion of the degenerative cascade (patients with the lower grades of degeneration). Group 2: the percentage of a very uncomfortable LBP in this group was 24%, and the number of the recurrences was 2 (5%) and in only 1 case we performed a new surgical procedure. The maximum amount of blood lost in both group was 80 cc and the mean time of the surgical procedure was 28 minutes (from 18 to 37) in the group 1 and 41 minutes (from 34 to 46) in the group 2. Conclusion The close observation of the right indications and the proper selection of patients is strictly recommended. The mininvasive and relatively easy surgical procedure do not induce the surgeons of an indiscriminate use of this device. The wrong level implant is the mast frequent mistake. From the observation of these very important points we believe that are obtained this very good results even should be necessary a big number of case study, a longer follow up and a randomized multicenter study. The absence of major complications, the minimally invasive surgical procedure and the good clinical results allow us to say that with a correct patient selection we can prevent that this disease from acute becomes chronic, and thus its natural progression. Last but not least if we performed this surgical procedure in the earliest stages of the degenerative cascade, we can reverse its trend.