Biomechanical Disturbances Research Articles

Biomechanical analysis of statics and gait of patients with patellofemorale pain syndrome

Patellofemoral pain syndrome (PFPS) is a pathology in the knee joint, which is often observed in young active people and manifests itself as pain in the knee and periarticular tissues in the absence of intra-articular pathology of the knee joint. The article presents the results of a biomechanical study of statics and walking in 47 patients with PFPS and 34 healthy individuals. Differences in goniometric parameters were revealed in patients and healthy individuals when walking. It has been demonstrated that in PFPS, biome-chanical disturbances affect both lower extremities. It has been shown that the severity of biomechanical disorders when walking can serve as a predictor of the effectiveness of conservative therapy for PFPS.

Chronic back pain as a spinal osteoarthritis manifestation: rationale and practice of symptomatic slow acting drugs for osteoarthritis use

Chronic non-specific back pain (CNBP) is the most common pathology of the musculoskeletal system, affecting from 10 to 60% of the adult population in the world, causing severe suffering, disability and a significant deterioration in the quality of life. Osteoarthritis (OA) should be considered as one of the main reasons of the development of CNBP – inflammatory and degenerative changes in the facet and sacroiliac joints, as well as the spinal column itself (in particular, osteitis of the Modic 1 type). Spinal OA is accompanied by biomechanical disturbances, nociplastic (peripheral and central sensitization) and psycho-emotional changes that form a complete picture and various CNBP phenotypes.Recognizing the leading role of OA as the cause of CNBP, it is advisable to use the same therapeutic approaches in this syndrome as in OA of peripheral joints. In particular, it is necessary to consider the use of symptomatic slow acting drugs for osteoarthritis (SYSADOA) in CNBP as the main pathogenetic therapy.Alflutop is one of the most popular parenteral SYSADOA widely used in Russian practice. This drug has a good evidence base: this review presents data from 12 clinical trials of Alflutop in CNBP (n=1479), which confirmed its efficacy and safety.

The Changing Face of the Cornea in a Case of Juvenile Glaucoma and Subclinical Keratoconus.

We report on a 23-year-old man who presented with bilateral subclinical keratoconus and juvenile glaucoma (JG). With intraocular pressures (IOPs) of 30 and 28 mmHg, both eyes were consecutively operated by adjusted trabeculotomy, leading to a remarkable decrease in IOP to well below the mean for this surgery in JG. Meanwhile, most keratoconus indices clearly progressed in the first 5 months postoperatively, with increases in corneal hysteresis, associated with a remarkable drop in the corneal resistance factor. During the following years, IOP remained low, and all changes (except the increase in corneal hysteresis) reverted to near preoperative levels through the follow-up course of 5 years. This report complements a few existing reports that show the coincidence of keratoconus and JG, and, more importantly, documents a novel pattern of remarkable and prolonged corneal changes following surgical lowering of IOP in eyes with these changes. Postoperative biomechanical disturbances in the cornea and possibly limbus are proposed in cases of JG and subclinical keratoconus.

Idiopathic scoliosis as a multifactorial disease: systematic review of current literature

Objective.To analyze the current literature dedicated to the etiopathogenesis and development of idiopathic scoliosis.Material and Methods.The analysis includes studies on the etiological factors of idiopathic scoliosis. The search was carried out on eLibrary, PubMed and Google Scholar databases. The review includes research and experimental studies, as well as systematic reviews and meta-analyses. The exclusion criterion is a theoretical work without practical research/experiment to confirm the theory. The depth of analysis is 30 years.Results.Out of 456 papers on the research topic, 153 were selected as meeting the inclusion/exclusion criteria. The main theories of the occurrence of idiopathic scoliosis are identified: genetic, neurogenic, theory of bone and muscle tissue defects, biomechanical, hormonal, evolutionary, and the theory of environmental and lifestyle influences.Conclusions.The term “idiopathic scoliosis” combines a number of diseases with different etiopathogenetic mechanisms of development. Idiopathic scoliosis has a polygenic inheritance. Different genes are responsible for its occurrence in different populations, and the progression mechanisms are triggered by various epigenetic factors. Bone and muscle tissue defects, pathology of the central nervous system, biomechanical disturbances, hormonal and biochemical abnormalities may play a dominant role in some cases of idiopathic scoliosis.

Cam morphology but neither acetabular dysplasia nor pincer morphology is associated with osteophytosis throughout the hip: findings from a cross-sectional study in UK Biobank

SummaryObjectivesTo examine whether acetabular dysplasia (AD), cam and/or pincer morphology are associated with radiographic hip osteoarthritis (rHOA) and hip pain in UK Biobank (UKB) and, if so, what distribution of osteophytes is observed.DesignParticipants from UKB with a left hip dual-energy X-ray absorptiometry (DXA) scan had alpha angle (AA), lateral centre-edge angle (LCEA) and joint space narrowing (JSN) derived automatically. Cam and pincer morphology, and AD were defined using AA and LCEA. Osteophytes were measured manually and rHOA grades were calculated from JSN and osteophyte measures. Logistic regression was used to examine the relationships between these hip morphologies and rHOA, osteophytes, JSN, and hip pain.Results6,807 individuals were selected (mean age: 62.7; 3382/3425 males/females). Cam morphology was more prevalent in males than females (15.4% and 1.8% respectively). In males, cam morphology was associated with rHOA [OR 3.20 (95% CI 2.41–4.25)], JSN [1.53 (1.24–1.88)], and acetabular [1.87 (1.48–2.36)], superior [1.94 (1.45–2.57)] and inferior [4.75 (3.44–6.57)] femoral osteophytes, and hip pain [1.48 (1.05–2.09)]. Broadly similar associations were seen in females, but with weaker statistical evidence. Neither pincer morphology nor AD showed any associations with rHOA or hip pain.ConclusionsCam morphology was predominantly seen in males in whom it was associated with rHOA and hip pain. In males and females, cam morphology was associated with inferior femoral head osteophytes more strongly than those at the superior femoral head and acetabulum. Further studies are justified to characterise the biomechanical disturbances associated with cam morphology, underlying the observed osteophyte distribution.

Early correction of malunited supracondylar humerus fractures in young children

IntroductionSupracondylar fracture malunion usually results in cubitus varus deformity. The long-standing unsightly deformity causes psychological stress to the child and his/her parents in addition to biomechanical disturbances and functional disorders in the affected elbow. The optimal timing of corrective osteotomy is not well-established in the literature. The present study aimed to report the results of early correction of cubitus varus deformity using a simple technique and to focus on the timing of early correction after supracondylar fracture malunion. Patients and MethodsThirty consecutive patients treated for recent cubitus varus deformity after malunited supracondylar fractures, in the period between January 2012 and August 2017, were retrospectively reviewed. All patients had early surgical correction of the deformity within one year after the initial injury. In patients who presented with maluniting supracondylar fracture, the fracture was splinted until union was achieved, then active exercises were encouraged until elbow ROM was regained. The deformity was then corrected with a lateral closing wedge (LCW) osteotomy and fixed with two lateral and one medial wire. ResultsAll the osteotomies united. All the deformities were corrected. The humerus-elbow-wrist (HEW) angle significantly improved compared to the pre-operative values (p<0.001). All patients achieved satisfactory results at the final evaluation. Twenty-six patients (86.7%) achieved excellent results while four patients (13.3%) achieved good results. ConclusionEarly correction of cubitus varus deformity avoids the psychological stress of the long-standing unsightly deformity to the young child and his/her family. It also avoids the delayed biomechanical and functional disturbances to the affected elbow. The LCW osteotomy and the three-wires fixation technique are simple and effective to correct the deformity and maintain the correction.

Problems in the Revision of Failed Moore Prosthesis

Over the years, Moore prosthesis has been described as a good option in the treatment of femoral neck fracture. Its main disadvantages are about femoral fixation and the acetabular erosion. Because of less cost, it still be used improperly and provide a large number of failures. Improper placement of the Moore prosthesis provide biomechanical disturbances of the arthroplasty. The insufficient of residual femoral neck length or the insufficient of metaphyseal fill are associated with the failure of the Moore arthroplasty. The aim of our study is to report and evaluate intraoperative findings and difficulties while we were convert failed aseptic Moore hemiarthroplasty into cemented total hip arthroplasty.

Comparison between two rabbit models of posttraumatic osteoarthritis: A longitudinal tear in the medial meniscus and anterior cruciate ligament transection

Animal osteoarthritis (OA) models have been developed to understand OA progression and evaluate new OA therapies. However, individual variations in joint lesions remain a critical problem in most current OA models. We established a novel rabbit model by creating a longitudinal tear in the medial meniscus body that was reproducible and similar to posttraumatic biomechanical disturbances in human OA. New Zealand rabbits underwent surgery and were assessed for 9 weeks. The rabbits were randomized into the sham control, medial meniscal tear (MMT), and anterior cruciate ligament transection (ACLT) groups. The animals were sacrificed at 4, 6, and 9 weeks posttreatment. The knee joints were harvested for histological and gene expression assessments. Both the MMT and ACLT procedures led to time-dependent degenerative changes in the femoral condyle cartilage. At each time point, the MMT group cartilage showed more severe degenerative changes than did the ACLT group cartilage. Consistently, inflammatory cytokine and catabolic gene expression were significantly higher, and anabolic gene expression was significantly lower in the MMT group than in the ACLT group. MMT treatment caused more severe structural damage to the cartilage and higher catabolic gene expression levels than the ACLT model at each time point. The MMT model may be highly beneficial in investigating posttraumatic OA (PTOA) development, especially PTOA from a meniscal injury. The MMT model replicated key features of human PTOA, including meniscal lesions, inflammatory responses, and the progression to osteoarthritic cartilage degeneration, thereby providing an exciting new avenue for translating promising treatments to clinical practice.

ПРИМЕНЕНИЕ КИНЕЗИОТЕЙПИРОВАНИЯ ПРИ ЗАДНЕМ ШЕЙНОМ СИМПАТИЧЕСКОМ СИНДРОМЕ

The objective. To substantiate the use of kinesiotaping in the complex treatment of patients with posterior cervical sympathetic syndrome based on clinical studies. Patients and methods. The dynamics of dizziness was assessed using the DHI dizziness rating scale (Dizziness Handicap Inventory) and the VRBQ (Vestibular Rehabilitation Benefit Questionnaire) vestibular questionnaire among 60 patients, and headache and neck pain dynamics were assessed using a visual analogue scale (VAS) to assess the dynamics of complaints of tinnitus, blurring of vision, nausea, vomiting, heart attacks, decreased concentration and attention were used by the International Classification of Functioning, Disability and Health (ICF), to evaluate the dynamics of blood flow, we used duplex scanning of the brachycephalic arteries, to assess anxiety self-assessment scale Sheehan anxiety, for assessing depression Beck depression scale. Results. In the kinesiotaping group, statistically reliable data were obtained (p&lt;0.05) for reducing dizziness, headache, cervical pain, a decrease in tinnitus, defocusing of vision, and a decrease in concentration and attention. Statistically reliable data were obtained (p&lt;0.05) for improving linear blood flow velocities (Vm, Vps) on the left vertebral artery at an extracranial level. Statistically reliable data were obtained (p&lt;0.05) for the effectiveness of kinesiotaping for the correction of upper cross syndrome. Conclusion. The use of kinesiotaping can be recommended for the correction of biomechanical disturbances, correction of the upper cross syndrome, as well as for the treatment of patients with posterior cervical sympathetic syndrome and increase in linear blood flow velocities through the vertebral arteries.

Analysis of the dynamics of the structural changes development in the humerus of guinea pigs under modeling biomechanical disturbances

Today, the role of the traumatic factor and inflammation in the development and progression of osteoarthrosis is generally recognized, but the available research results do not allow to establish the role of impaired biomechanics as a monofactor in the development of deforming ostearthrosis of the shoulder joint. Violation of the function of the bone and bone-cartilage elements of the joint, which is compensated by soft tissue formations, leads to overloads of the joints, upsets the normal balance of the load forces in the joint, creates abnormal biomechanics and the resulting pathological manifestations of deforming osteoarthrosis. The aim of the study is research of the dynamics of the disturbed biomechanics influence of the shoulder joint on the development of deformation osteoarthrosis and the features of the development of its structural changes. The experiments were conducted on guinea pigs weighing 380-420 grams at the age of 5 months. A model of surgical restriction of joint mobility was reproduced, which caused the formation of contracture. Using the methods of histology and scanning electron microscopy, we studied the relief of the articular surface, the topography of degenerative changes, and structural changes in the articular cartilage and subchondral bone. A statistical evaluation of the obtained data samples was carried out using Student t-test. The results were considered reliable at р&lt;0.05. The results of an experimental study demonstrated a decrease in the thickness and structure of articular cartilage when modeling deforming osteoarthrosis and confirmed the hypothesis that pathological limitation of the mobility of the shoulder joint and violation of biomechanics is an independent factor in the formation of osteoarthrosis. After surgery on day 30, degenerative changes and their progression with the formation of contracture on day 90 of observation were found in the articular cartilage. The features of the development of articular surface degeneration, the dynamics of the pathological changes and topography, which can expand the understanding of the pathogenesis of the disease, were established. The loss of the superficial zone caused the progression of dystrophic changes in the articular cartilage and sclerosis of the subchondral bone at 60 and 90 days.

Trunk and neck movements are reduced in people with chronic neck pain when walking along a curved trajectory

Purpose: Humans are regularly faced with changes in path direction during everyday life (Segal et al. 2008), yet few studies evaluate gait along curved trajectories. Given the importance of neck sensorimotor control during walking and turning (Imai et al. 2001) it is clinically relevant to consider the impact of neck pain which may impose neuromuscular and biomechanical disturbances affecting the ability to walk along rectilinear as well as curvilinear trajectories. This study examined the control of trunk and neck motion during walking along rectilinear and curvilinear trajectories in people with chronic neck pain versus asymptomatic control subjects.

An in vitro analysis of injectable methacrylated alginate cryogels incorporated with PRP targeting minimally invasive treatment of bone nonunion

The macroporous structure and high interconnectivity of cryogels supports fluid flow, cell mobility, and angiogenesis throughout the scaffold. Additionally, a pre-formed injectable cryogel allows the potential for minimally invasive treatment of bone nonunions that would normally require surgical intervention. Such a defect is due to compromised signaling pathways by biological or biomechanical disturbance during fracture healing. The addition of powdered platelet-rich plasma (PRP) introduces soluble factors normally found in the early inflammatory stages of bone healing, allowing the bone to restart the healing process with the cryogel scaffold as a template for bone formation. A physical characterization of methacrylated alginate (MAA) and PRP-loaded cryogels was performed to determine the most suitable fabrication methods for bone applications. Further investigations were performed to assess cell proliferation and infiltration of MG-63 cells on the scaffolds, the rate of PRP elution, and the bioactive molecules being eluted at various time points. In this study, it was found that higher concentrations of PRP and MAA caused an increase in mechanical stiffness; compromising the shape memory properties of the cryogel. However, the addition of freeze-thaw cycles increased the porosity of the matrix while providing a more compressible scaffold that eluted PRP at a faster rate.

Spine and lower extremity kinematics during gait in patients with cervical spondylotic myelopathy

Background ContextCervical spondylotic myelopathy (CSM) typically manifests with a slow, progressive stepwise decline in neurologic function, including hand clumsiness and balance difficulties. Gait disturbances are frequently seen in patients with CSM, with more advanced cases exhibiting a stiff, spastic gait. PurposeTo evaluate the spatiotemporal parameters and spine and lower extremity kinematics during the gait cycle of adult patients with CSM before surgical intervention. Study DesignProspective cohort study. Patient SampleTwenty-eight subjects with symptomatic CSM who have been scheduled for surgery and 30 healthy controls (HC). Outcome MeasuresSpine and lower extremity kinematics and spatiotemporal parameters. MethodsClinical gait analysis was performed for patients with CSM and HC. The data were analyzed with a one-way analysis of variance. ResultsPatients with CSM have significantly more anterior pelvis tilt (CSM: 13.97°, HC: 5.56°), larger lumbar lordosis (CSM: 8.59°, HC: 2.7°), smaller cervical lordosis (CSM: 6.02°, HC: 11.35°), and less head flexion (CSM: 0.69°, HC: 8.66°) at the beginning of the gait cycle. There was a decrease in knee range of motion in patients with CSM compared with controls (CSM: 36.31°, HC: 50.17°). Furthermore, patients with CSM presented with slower walking speed (CSM: 0.81 m/s, HC: 1.05 m/s), decreased cadence (CSM: 95.57 step/m, HC: 107.64 step/m), increased double support time (CSM: 0.40 s, HC: 0.28 s) and stride time (CSM:1.28 s, HC: 1.13 s), shorter stride length (CSM: 1.04 m, HC: 1.18 m) and step length (CSM:0.51 m, HC: 0.58 m), and wider width (CSM: 0.14 m, HC:0.11 m). ConclusionsOur study shows that patients with CSM enter the gait cycle with a larger anterior pelvic tilt and lumbar lordosis as well as less cervical lordosis and head flexion. As a consequence of these abnormal spinal parameters at the onset of the gait cycle, lower extremity biomechanics are also altered. Our study is the first to demonstrate the relationship between aberrant spinal alignment and lower extremity function. Identification of this interrelationship as well as the specific gait and biomechanical disturbances seen in myelopathic patients can both inform our understanding of the disease and tailor rehabilitation protocols.

ДИНАМИКА ПОСТУРАЛЬНОГО БАЛАНСА В ВЕРТИКАЛЬНОЙ ПОЗЕ ТХЭКВОНДИСТОВ ВЫСОКОЙ КВАЛИФИКАЦИИ В ГОДОВОМ МАКРОЦИКЛЕ

Сарайкин Дмитрий Андреевич, кандидат биологических наук, доцент, доцент кафедры безопасности жизнедеятельности и методико-биологических дисциплин, Южно-Уральский государственный гуманитарно-педагогический университет, г. Челябинск, saraykind@cspu.ru. Епишев Виталий Викторович, кандидат биологических наук, доцент, доцент кафедры теории и методики физической культуры и спорта, Институт спорта, туризма и сервиса, Южно- Уральский государственный университет, г. Челябинск, epishev74@mail.ru. Павлова Вера Ивановна, доктор биологических наук, профессор, профессор кафедры безопасности жизнедеятельности и методико-биологических дисциплин, Южно-Уральский государственный гуманитарно-педагогический университет, г. Челябинск, pavlovavi@cspu.ru. Камскова Юлиана Германовна, доктор медицинских наук, профессор, профессор кафедры безопасности жизнедеятельности и методико-биологических дисциплин, Южно-Уральский государственный гуманитарно-педагогический университет, г. Челябинск, kamskovaug@cspu.ru. D.A. Saraykin1, saraykind@cspu.ru, V.V. Epishev2, epishev74@mail.ru, V.I. Pavlova1, pavlovavi@cspu.ru, Y.G. Kamskova1, kamskovaug@cspu.ru 1South Ural State Humanitarian Pedagogical University, Chelyabinsk, Russian Federation, 2South Ural State University, Chelyabinsk, Russian Federation

A Multicenter Study of Early Anti-inflammatory Treatment in Patients With Acute Anterior Cruciate Ligament Tear

Background: It is increasingly recognized that biochemical abnormalities of the joint precede radiographic abnormalities of posttraumatic osteoarthritis (PTOA) by as much as decades. A growing body of evidence strongly suggests that the progression from anterior cruciate ligament (ACL) injury to PTOA is multifactorial, involving the interplay between biomechanical disturbances and biochemical homeostasis of articular cartilage. Purpose: The purposes of this randomized study using an acute ACL injury model were to (1) evaluate the natural progression of inflammatory and chondrodegenerative biomarkers, (2) evaluate the relationship between subjective reports of pain and inflammatory and chondrodegenerative biomarkers, and (3) determine if postinjury arthrocentesis and corticosteroid injection offer the ability to alter this biochemical cascade. Study Design: Randomized controlled trial; Level of evidence, 2. Methods: A total of 49 patients were randomized to 4 groups: group 1 (corticosteroid at 4 days after ACL injury, placebo injection of saline at 2 weeks), group 2 (placebo at 4 days after ACL injury, corticosteroid at 2 weeks), group 3 (corticosteroid at both time intervals), or a placebo group (saline injections at both time intervals). Patient-reported outcome measures and synovial biomarkers were collected at approximately 4 days, 11 days, and 5 weeks after injury. The change between the time points was assessed for all variables using Wilcoxon tests, and the relationship between changes in outcome scores and biomarkers were assessed by calculating Spearman ρ. Outcomes and biomarkers were also compared between the 4 groups using Kruskal-Wallis tests. Results: No adverse events or infections were observed in any study patients. With the exception of matrix metalloproteinase 1 (MMP-1) and tumor necrosis factor–inducible gene 6 (TSG-6), chondrodegenerative markers worsened over the first 5 weeks while all patient-reported outcomes improved during this time, regardless of treatment group. Patient-reported outcomes did not differ between patients receiving corticosteroid injections and the placebo group. However, increases in C-telopeptide of type II collagen (CTX-II), associated with collagen type II breakdown, were significantly greater in the placebo group (1.32 ± 1.10 ng/mL) than in either of the groups that received the corticosteroid injection within the first several days after injury (group 1: 0.23 ± 0.27 ng/mL [P = .01]; group 3: 0.19 ± 0.34 ng/mL [P = .01]). Conclusion: PTOA begins at the time of injury and results early on in dramatic matrix changes in the knee. However, it is encouraging that early intervention with an anti-inflammatory agent was able to affect biomarkers of chondral degeneration. Should early intervention lead to meaningful changes in either the onset or severity of symptomatic PTOA, the current treatment paradigm for patients with ACL injury may have to be restructured to include early aspiration and intra-articular intervention. Trial Registration: ClinicalTrials.gov identifier: NCT01692756.

Neuromuscular deficits after peripheral joint injury: a neurophysiological hypothesis.

In addition to biomechanical disturbances, peripheral joint injuries (PJIs) can also result in chronic neuromuscular alterations due in part to loss of mechanoreceptor-mediated afferent feedback. An emerging perspective is that PJI should be viewed as a neurophysiological dysfunction, not simply a local injury. Neurophysiological and neuroimaging studies have provided some evidence for central nervous system (CNS) reorganization at both the cortical and spinal levels after PJI. The novel hypothesis proposed is that CNS reorganization is the underlying mechanism for persisting neuromuscular deficits after injury, particularly muscle weakness. There is a lack of direct evidence to support this hypothesis, but future studies utilizing force-matching tasks with superimposed transcranial magnetic stimulation may be help clarify this notion.

Upper Palaeolithic archaeobotany of Ghar-e Boof cave, Iran: a case study in site disturbance and methodology

The excavation of Ghar-e Boof, a cave in the Zagros Mountains, places the site not only at the center of discussion on the transition to and development of its regional lithic tradition: the Rostamian (37,000–31,000 BP), but also in differentiating between plants used by humans or mere traces of the surrounding vegetation. The large pulses of Lathyrus or Vicia sp. recovered from this shallow cave in the southwest of Iran may, for instance, represent food collected from wild stands already in the early Upper Palaeolithic. The seeds of barley (Hordeum sp.), although not all clearly domesticated, are without doubt signs of disturbance or bioturbation since the historic era. Analysis of cave deposits over 30,000 years old raise a number of methodological and interpretive challenges. Human, taphonomic, or biomechanical disturbances impact the deposition of plant remains, as well as affect the composition of the assemblages, undermining spatial and ecological examination of the data set. Comprehension of provenance of the samples, site genesis, and matrix development, through detailed micromorphological and stratigraphical studies, is thus suggested in conjunction with the archaeobotanical analyses, to identify disturbances, define their cause, and treat them appropriately. Numerical studies and ecological interpretations of climate, vegetation composition, or indications of human activity therefore follow specific criteria discussed here. Despite signs of disturbance in the plant assemblages, archaeobotanic research can lead to recognition of environmental conditions, plausible human subsistence, site use and seasonality, and sound vegetation description.

Association Between Leg Length Discrepancy and Posterior Tibial Tendon Dysfunction

Leg length discrepancy (LLD) is associated with a variety of orthopaedic disorders and biomechanical gait changes that involve possible overload of the posterior tibial tendon (PTT). In view of the biomechanical disturbances induced by LLD, an association may exist between LLD and PTT dysfunction (PTTD). To compare the frequency and magnitude of LLD between subjects with and without PTTD and ascertain whether associations exist between clinical features and presence of dysfunction. Case-control study. A total of 118 patients with a diagnosis of PTTD were seen between January 2009 and September 2012 and compared with 118 gender-matched and race-matched volunteers. The frequency of LLD, the mean absolute LLD, and the mean relative LLD were measured by conventional (radiographic) or computed tomography scanography and compared between cases and controls. The prevalence of LLD and mean absolute and relative LLD values were significantly greater in the case group (94.9%, 5.64 mm and 7.36%, respectively) than in the control group (79.7%, 3.28 mm and 4.18%, respectively) (P < .001). The findings of this study demonstrate a relationship between LLD and PTTD. In light of the major biomechanical changes it induces, LLD may be a predisposing factor for development of PTTD.

Differential diagnosis of back pain in adult scoliosis (non operated patients)

The relationship between back pain and scoliosis is not clear. Old long-term follow-up studies reported no greater incidence or degree of back pain in adult scoliosis than in normal population when matched for age and sex. At the end of the seventies studies were contradictories. While Fowles et al (1978) concluded that untreated scoliosis could be considered as a disabling disease in the adult particularly after the age of 30, Nachemson (1979) reported a minimal risk of disabling back pain in adult patients with lumbar curves stating that ‘whether severe low back pain occurs more often in adults who have lumbar curves than in those whose spines are straight is open to question’. Later, in 1981, Weinstein et al found that backache was more common in scoliosis patients than in the general population with no relation between back pain and the presence of osteoarthritic changes. Kostuik and Ventivoglio (1981) reported a similar incidence of low back pain (59%) in subjects with lumbar or thoracolumbar curves and normal population. However, they found a correlation between back pain and severity of the curve especially for curves of more than 45°, while patients with no pain tended to have smaller curves. Jackson et al (1983) confirmed that incidence was comparable between adult scoliosis and general population but severity was greater in scoliotic patients. They found that patients with lumbar curve had more pain. Compensatory lumbosacral curves were most painful and disabling. The controversy about how well or bad scoliosis population do it (pain and function) during adult life still continued during the nineties and while the results from the Ste-Justine Adolescent Idiopathic Scoliosis Cohort Study suggested that back pain is responsible for a considerable amount of disability and handicap in later life, the revisited sample from Weinstein et al, showed that untreated late onset idiopathic scoliosis causes little physical impairment other than back pain and cosmetic concerns, with these patients being productive and functional at high level at 50-year follow up. In agreement with the Ste-Justine’s study, Schwab F et al (2003) studied the effect of scoliosis in the self-perception of health and showed that patients in this study averaged scores (SF-36) much lower than the norm from both the general US population in all 8 categories and the US population for ages 55-64 in 7 out of 8 categories of the SF-36 questionnaire. Whether or not idiopathic scoliosis developed during growth will alter health related quality of life later and how conservative and/or surgical treatment will change its natural history is something needing further research, however, from a practical point of view, here the question is not that but how scoliosis condition affects the diagnose, prognosis and management of adult patients suffering from chronic back pain. Adult patients attending our institution - a scoliosisspecific rehabilitation centre - could be divided in two main groups: Group I: Patients attending the clinic with a clear self-conscience of belonging to the scoliosis population because they were mostly diagnosed during childhood or during adolescence – treated or not treated-; Group II: Patients belonging to the back pain population referred to us by their doctors, mostly because they showed a bad response to general rehabilitation and such a bad response was related to a non previously diagnosed scoliosis condition. Generally speaking we could identify patients with idiopathic, congenital and secondary scoliosis in Group I while most of the patients in Group II have developed de novo degenerative scoliosis or scoliosis secondary to any pelvic or lower limbs biomechanical disturbance. The main reasons for consultation in Group I are: documented curve progression, cosmesis, chronic back pain and disability, and prevention in patients that have been followed-up

Intacs to stabilize diurnal variation in refraction after radial keratotomy

We present a patient who was dissatisfied with the refractive results of the radial keratotomy procedure he had 8 years previously, specifically the instability of the visual acuity and refractive error throughout the day. To reverse the biomechanical disturbance caused by the incisions, an intracorneal ring segment (Intacs, Addition Technology, Inc.) was inserted in the inferior cornea. The variation in refraction decreased from 1.50 and 2.25 diopters (D) to 0.25 and 0.50 D, resulting in a very satisfied patient.