Increase In Anterior Pelvic Tilt Research Articles

Anterior pelvic tilt increases hamstring strain and is a key factor to target for injury prevention and rehabilitation.

Hamstring muscle strain injury is very common in sports involving high-speed running. Hamstring muscles originate from the ischial tuberosity and thus pelvic position may influence hamstring strain during different sports movements like sprinting, but this has only been evaluated by indirect methods. This study tested the hypothesis that a change in anterior pelvic tilt causes elongation of the overall hamstring complex and disproportionately elongates proximal relative to distal muscle regions. Seven fresh-frozen specimens (full lower limb with pelvis and lumbar spine) were used for this in vitro study. Specimens were dissected to enable visualization of the hamstring muscles and then fixed into a custom-made testing bench that allowed controlled movement of the pelvis over a fixed femur and tibia. Nine markers were inserted into the hamstring muscles to allow intra- and intermuscle difference measurements. Then, six different anterior pelvic angles were used to measure the difference in hamstring muscle lengthening through a three-dimensional reconstruction system based on stereoscopic machine vision technology. An increase in anterior pelvic tilt produced a significant non-uniform increase in tissue elongation in all regions of the three hamstring muscles (semitendinosus, semimembranosus [SMB] and biceps femoris long head), which was greater in the proximal (>1 cm every 5°) compared to the distal region (≈0.4 cm every 5°). At the proximal hamstring region, SMB showed significantly greater length changes compared to conjoint tendons with nonstatistically significant elongation differences between muscles at the distal region. Considering the results of the study, the pelvis segment will likely play a fundamental role as a strain regulator of hamstring muscles. These results will have an impact on injury rehabilitation and prevention processes of hamstring injuries, as well as optimize future musculoskeletal models and avoid potential underestimation of the hamstring muscle-tendon complex lengthening during high-speed running. N/A.

Does patella lowering as part of multilevel surgery improve knee kinematics in children with cerebral palsy and crouch gait? A meta-analysis of comparative studies.

To evaluate differences in knee kinematic outcomes of patellar-lowering surgery, specifically patellar tendon advancement or patellar tendon shortening, compared with no-patellar-lowering surgery in multilevel surgery for children with cerebral palsy and crouch gait. Four databases were searched to retrieve studies published from inception until 2023. Three reviewers independently screened for studies with observational or randomized control designs, comparing two groups of patients with cerebral palsy and crouch gait who underwent multilevel surgery (with patellar-lowering surgery versus no-patellar-lowering surgery), where various gait analysis outcomes were reported (CRD42023450692). The risk of bias was assessed with the Risk Of Bias In Non-randomised Studies - of Interventions (ROBINS-I) tool. Seven studies (249 patients and 368 limbs) met the eligibility criteria. Patients undergoing patellar-lowering surgery demonstrated statistically significant improvements in knee flexion at initial contact (mean difference = -6.39; 95% confidence interval = [-10.4, -2.75]; p = 0.0006; I2 = 84%), minimum knee flexion in stance (mean difference = -14.27; 95% confidence interval = [-18.31, -10.23]; p < 0.00001; I2 = 89%), and clinical knee flexion contracture (mean difference = -5.6; 95% confidence interval = [-9.59, -1.6]; p = 0.006; I2 = 95%), with a significant increase in anterior pelvic tilt (mean difference = 2.97; 95% confidence interval = [0.58, 5.36]; p = 0.01; I2 = 15%). However, improvements in gait deviation index and decrease in peak knee flexion in swing did not reach statistical significance. Subgroup analysis reduced heterogeneity and revealed (1) greater improvement using patellar tendon shortening versus patellar tendon advancement techniques; (2) lack of knee flexion contracture improvement in high-quality or longer-term studies; (3) longer-term improvement only in minimum knee flexion in stance, with a decrease in peak knee flexion in swing; and (4) an inability to assess the potential benefit of rectus femoris procedure and hamstring preservation. Overall, the combination of patellar-lowering surgery with multilevel surgery demonstrated superior improvements in stance-phase knee kinematics compared with multilevel surgery alone, despite an increase in anterior pelvic tilt and a longer-term knee flexion reduction during the swing phase. Level III, Systematic review of level III studies.

Persistent increase in anterior pelvic tilt after hamstring lengthening in children with cerebral palsy

BackgroundHamstring lengthening has traditionally been the surgical treatment of choice to correct flexed knee gait in children with cerebral palsy (CP). Improved passive knee extension and knee extension during gait are reported post hamstring lengthening, but concurrent increased anterior pelvic tilt also occurs. Research questionDoes anterior pelvic tilt increase after hamstring lengthening in children with CP both in the short-term and mid-term, and what predicts increased post-operative anterior pelvic tilt? Methods44 participants were included (age 7.2, SD 2.0 years; 5 GMFCS I, 17 GMFCS II, 21 GMFCS III, 1 GMFCS IV). Mean pelvic tilt was compared between visits, and the effect of potential predictors of change in pelvic tilt was examined using linear mixed models. The relationship of change in pelvic tilt to change in other variables was examined using Pearson correlation. ResultsAnterior pelvic tilt increased significantly post-operatively by 4.8° (p < 0.001). It remained significantly higher by 3.8° at 2–15 years follow-up (p < 0.001). Change in pelvic tilt was not affected by sex, age at surgery, GMFCS level, assistance during walking, time since surgery, or baseline values of hip extensor strength, knee extensor strength, knee flexor strength, popliteal angle, hip flexion contracture, step length, walking speed, maximum hip power in stance, or minimum knee flexion in stance. Pre-operative dynamic hamstring length was associated with greater anterior pelvic tilt at all visits but did not affect amount of change in pelvic tilt. Patients in GMFCS I-II showed a similar pattern of change in pelvic tilt to GMFCS III-IV. SignficanceWhen considering hamstring lengthening for ambulatory children with CP, surgeons should weigh increased mid-term anterior pelvic tilt post-operatively with the desired outcome of improved knee extension in stance. Patients with neutral or posterior pelvic tilt and short dynamic hamstring lengths pre-operatively have lowest risk of excessive post-operative anterior pelvic tilt

The relationship between pelvic tilt, frontal, and axial leg alignment in healthy subjects

IntroductionThe relationship between anterior pelvic tilt and overall sagittal alignment has been well-described previously. However, the relationship between pelvic tilt, frontal, and axial leg alignment remains unclear. The aim of the study was to analyze the relationship between pelvic tilt and frontal and axial leg alignment in healthy subjects. Material and methodsThirty healthy subjects (60 legs) without prior surgery underwent standing biplanar long leg radiograph. Pelvic parameters (pelvic tilt, pelvic incidence, sacral slope), hip-knee-ankle angle (HKA), femoral antetorsion and tibial torsion were measured using SterEOS (EOS Imaging) software. EOS was acquired with the feet directing straight anteriorly, which corresponds to a neutral foot progression angle (FPA). The influence of HKA, femoral antetorsion, tibial torsion and gender on pelvic tilt was analyzed in a univariate correlation and multiple regression model. ResultsSixteen female subjects and 14 male subjects with a mean age of 27.1 years ± 10 (range 20–67) were included. HKA, femoral antetorsion, and tibial torsion correlated with anterior pelvic tilt in univariate analysis (all p < 0.05). Anterior pelvic tilt increased 1.1° (95% CI: 0.7 to 1.5) per 1° of knee valgus (p < 0.001) and 0.5° (95% CI: 0.3 to 0.7) per 1° of external tibial torsion (p < 0.001). Overall, linear regression model fit explained 39% of variance in pelvic tilt by the HKA, femoral antetorsion and tibial torsion (R2 = 0.385; p < 0.001). ConclusionValgus alignment and increasing tibial torsion demonstrated a weak correlation with an increase in anterior pelvic tilt in healthy subjects when placing their feet anteriorly. The relationship between frontal, axial leg alignment and pelvic tilt needs to be considered in patients with multiple joint disorders at the hip, knee and spine. Alteration of the frontal, or rotational profile after realignment surgery or by implant positioning might influence the pelvic tilt when the FPA is kept constant.

Long-term outcome of hamstring lengthening versus transfer and the role of biceps femoris lengthening in patients with spastic diplegia and dynamic knee flexion in gait.

Orthopedic treatment of flexed-knee gait consists of hamstring lengthening along with surgery at other levels. Transfer of the semitendinosus (hamstring transfer) was introduced to avoid increase of anterior pelvic tilt as well as reduce risk of recurrence. We retrospectively assessed children with spastic cerebral palsy and flexed-knee gait pre-operatively, 1 year post-operatively, and at a minimum of 7 years post-operatively. The 39 patients were a mean 9.4 ± 3.4 years at the time of surgery, 20 subjects underwent hamstring transfer, and 19 subjects had hamstring lengthening with mean follow-up 9.1 years. Passive range of motion improved initially, but regressed at long term. Dynamic minimum knee flexion in stance decreased in both groups at the first post-operative study, and was maintained at final follow-up in 64-67% of patients. There was a small increase in anterior pelvic tilt at the 1-year follow-up which subsequently decreased to less than pre-operative in the hamstring lengthening group but remained mildly increased (5°) in the hamstring transfer group at final follow-up. Success in correcting stance knee flexion of the entire group was 69% of the Gross Motor Function Classification System grades I and II and 60% of the Gross Motor Function Classification System grade III subjects. Gait profile Score and sagittal knee Gait Variable Score both showed clinically important improvement after surgery and was mostly maintained long term for both groups. Lateral hamstring lengthening was beneficial in more severe patients, with minimal risk of adverse effects. Hamstring surgery as part of single event multi-level surgery (SEMLS) is effective in correcting flexed-knee gait in 60%-70% of patients with minimal effect on anterior pelvic tilt. There was no added advantage to hamstring transfer. Biceps Femoris lengthening may be beneficial and without significant additional risk. level III.

Pelvic Tilt and Range of Motion in Hips With Femoroacetabular Impingement Syndrome.

Physiotherapy is a management option for the treatment of femoroacetabular impingement (FAI) syndrome. This study examines the influence of changes in pelvic tilt and hip adduction on the range of motion (ROM) of the hip. Ten FAI hips were used to simulate impingement at two positions: (1) 20° internal rotation (IR) with 100° flexion and 10° adduction and (2) 40° IR with 35° flexion and 10° adduction; the amount of IR was measured at the point of bony impingement or to the defined limit. Each simulation was performed at neutral and 5° and 10° anterior and posterior pelvic tilt. Then, the hip was placed in 10° of abduction, and all simulations were repeated. With neutral pelvic tilt, impingement occurred at 4.3 ± 8.4° of IR at the high-flexion position. An increase in anterior pelvic tilt led to a loss of IR, that is, earlier occurrence of FAI, whereas an increase in posterior pelvic tilt led to an increase in IR, that is, later occurrence of FAI. At the high-flexion position, abduction provided more IR before impingement (neutral: 9.1 ± 5.7°, P < 0.01; 10° anterior tilt: 14.6 ± 5.2°, P < 0.01; 10° posterior tilt: 4.2 ± 3.7° IR, P = 0.01). Placing the hip in abduction and posteriorly tilting the pelvis produce a combined effect that increased IR relative to the neutrally tilted pelvis (5° posterior tilt: 11.4 ± 7.6°, P = 0.01; 10° posterior tilt: 12.8 ± 7.6°, P < 0.01). The ROM in the mid-flexion position was not affected by any combination of pelvic tilt and hip abduction or adduction (average IR: 37.4 ± 5.0°, P > 0.05). Abduction and posterior pelvic tilt increased the impingement-free ROM in the hips with FAI. Thus, rehabilitation aimed at altering the tilt of the pelvis may reduce the frequency of impingement and limit further joint damage.

The increase of anterior pelvic tilt after semitendinosus transfer to distal femur in patients with spastic diplegic cerebral palsy.

The aim of this study was to compare semitendinosus transfer to distal femur (STTX) to semitendinosus surgical lengthening (STL) regarding the increase of anterior pelvic tilt after flexed knee gait treatment. Thirty-nine patients were evaluated, and they were divided according surgical procedures at knees: STL group (22 patients/44 knees), which included patients who received medial hamstrings surgical lengthening as part of multilevel approach, and STTX group (17 patients/34 knees), which was represented by patients who underwent orthopedic surgery including a STTX instead of STL. In the present study, the mean anterior pelvic tilt increased in all groups after treatment and STTX was not effective to prevent it in a medium-term follow-up.

Pelvic Tilt Changes After Hamstring Lengthening in Children With Cerebral Palsy.

Flexion deformity of the knee is a common presentation in children with cerebral palsy with hamstring surgery as an option for addressing this. However, concerns with regard to increased pelvic tilt have been raised. The purpose of this study was to compare preoperative and postoperative pelvic tilt after isolated hamstring lengthening versus combined hamstring lengthening and the influence of Gross Motor Function Classification System (GMFCS) levels on pelvic tilt. This retrospective study included 46 ambulatory children with cerebral palsy who had had open medial hamstring lengthening (mean age at surgery, 11 y 11 mo; SD, 2 y 11 mo; GMFCS I, 16; GMFCS II 20; GMFCS III 10). Twelve children underwent isolated surgery and 34 children underwent combined surgery. The isolated hamstring procedures could be combined with foot and/or ankle-level surgery, as only the hamstring procedure would affect the pelvic tilt. Combined surgery was defined as hamstring lengthening with other procedures performed at the knee or more proximally. The preoperative and postoperative 3-dimensional gait analysis data were evaluated in this study. Both the isolated and combined hamstring lengthening groups showed no significant change in pelvic tilt ([INCREMENT]1.28, P=0.203; [INCREMENT]1.47, P=0.113, respectively). A significant change in pelvic tilt was seen in children functioning at GMFCS III ([INCREMENT]4.66, P=0.009) but not GMFCS I and II ([INCREMENT]0.37, P=0.718; [INCREMENT]0.48, P=0.697). Significant postoperative decreases in the knee flexion angle at initial contact were seen for both isolated ([INCREMENT]5.72, P=0.010) and combined hamstring lengthening ([INCREMENT]10.95, P<0.001). Hamstring lengthening, for the majority of patients, did not lead to a clinically significant change in mean pelvic tilt and improved knee flexion angle at initial contact. Children who functioned at GMFCS level III had an increase in anterior pelvic tilt and caution should be exercised in this group. Level IV evidence-case series.

Does Compensatory Anterior Pelvic Tilt Decrease After Bilateral Periacetabular Osteotomy?

The kinetic link among the lumbar spine, pelvic tilt, and the hip has been hypothesized, but this relationship requires further study in acetabular dysplasia. Anecdotal reports suggest that patients may compensate for acetabular dysplasia with an involuntary increase in anterior pelvic tilt; it is not known if this relationship is affected by acetabular reorientation. (1) Does compensatory pelvic tilt decrease on preoperatively obtained standing AP pelvis radiographs compared with those obtained at a minimum of 6 months after bilateral periacetabular osteotomy (PAO)? (2) Does a modified surrogate measurement of pelvic tilt, the pubic symphysis to sacroiliac (PS-SI) index, correlate with a physical synthetic bones model in which pelvic tilt can be directly measured? (3) Can the PS-SI index demonstrate high interrater reliability? We assessed the surgical records of one surgeon, who participates in the longitudinally maintained Academic Network of Conservational Hip Outcomes Research (ANCHOR) registry, for patients who had undergone the second side of a staged bilateral PAO between 2007 and 2016; there were 113 such patients. Of those, 70 (62%) were lost to followup within 6 months of the second PAO or did not have adequate imaging studies, and another three (3%) were excluded for prespecified reasons, leaving 40 (35%) for evaluation in this retrospective study. Standing preoperative and most recent postoperative AP pelvis radiographs were used to measure the Tönnis angle, anterior wall index, posterior wall index, lateral center-edge angle, pubis symphysis-to-sacrococcygeal junction distance, and the PS-SI index. The most recent radiographs were obtained at a mean of 16 ± 6 months after the second PAO. We chose 6 months as the minimum because at this time point, the majority of patients have reached their maximum clinical improvement and are no longer limited by postoperative muscle dysfunction. Statistical analysis was performed using the intraclass correlation coefficient (ICC) for interrater reliability and paired t-tests for assessing change in measurements from pre- to postoperative. Additionally, a model was created using a physical synthetic bones model in which pelvic tilt could be directly measured. This model was secured through bilateral acetabuli on a mount and rotated through 5° increases in pelvic tilt. AP pelvis radiographs were obtained at each point, the PS-SI index was measured, and a regression analysis performed to evaluate for trend. Overall, 37 of 40 patients (93%) had a decrease in pelvic tilt, as measured by the PS-SI index. The mean amount of pelvic tilt as measured by the PS-SI index decreased after surgery when comparing the preoperative with latest radiographs on this parameter (97 ± 14 mm versus 89 ± 13 mm, mean difference 8 ± 9 mm; 95% confidence interval, -11 to -5; range 17 increase to 24 decrease, p < 0.001). A linear relationship between pelvic tilt and PS-SI index (PS-SI index = 5.0° + 3.6° tilt, R = 0.99) was identified in the synthetic bones validation model. Finally, the interrater reliability was found to be excellent for the PS-SI index preoperatively (ICC = 0.986) and postoperatively (ICC = 0.988). We found a modest reduction in anterior pelvic tilt after bilateral PAO. This finding suggests that acetabular reorientation affects pelvic position. In clinical practice, patients with acetabular dysplasia may compensate with dynamic and reversible changes in pelvic tilt. The PS-SI index is a reproducible tool to measure the height of the pelvic inlet as an assessment of pelvic tilt. In the future, clinical studies should evaluate the clinical implications of these radiographic findings, including the assessment of back pain, which although multifactorial may be influenced by pelvic tilt. Level III, therapeutic study.

The increase of anterior pelvic tilt after crouch gait treatment in patients with cerebral palsy

BackgroundThe increase of anterior pelvic tilt (APT) has been described after the treatment of crouch gait in cerebral palsy (CP). The ideal treatment option for flexed knee gait in CP should provide knee extension improvement in the stance phase without generating the increase of APT. Research questionThe purpose of this study was to compare three different approaches used for the treatment of crouch gait in CP [distal femur extension osteotomy (DFEO), patellar tendon shortening (PTS) and the combination of DFEO +PTS] regarding the increase of APT after the interventions. MethodsThe inclusion criteria were: (1) diagnosis of spastic diplegic CP, (2) GMFCS levels I–III, (3) patients who underwent DFEO and/or PTS and (4) with complete documentation in the gait laboratory before and after the intervention. The included patients were divided into 3 groups, according to the procedures performed for crouch gait treatment: PTS (19 patients), DFEO (54 patients) and PTS + DFEO (22 patients). ResultsDuring stance phase, knee flexion decreased from 41.60 to 13.60 in the PTS group (p < 0.001), from 46.00 to 30.70 in the DFEO group (p < 0.001) and from 52.30 to 29.50 in the PTS + DFEO group (p < 0.001). APT increased 140 (p < 0.001) in the PTS group, 7.1° (p < 0.001) in the DFEO group and 6.60 (p < 0.001) in the PTS + DFEO group after surgical intervention. The PTS group presented a more significant deterioration of pelvic tilt than the DFEO (p = 0.002) and PTS + DFEO (p = 0.001) groups. The increase of APT was higher when HSL was also performed in the PTS + DFEO group (p = 0.016). SignificanceThe increase of APT was observed in all studied groups, but it was more significant for those who underwent a PTS. The inclusion of HSL in the surgical plan was related a higher increase of APT in the PTS + DFEO group.

Does additional patella tendon shortening influence the effects of multilevel surgery to correct flexed knee gait in cerebral palsy: A randomized controlled trial

BackgroundThe aims of this study were to investigate if patellar tendon shortening (PTS) as a part of SEMLS (single event multilevel surgery) is effective for reduction of flexed knee gait in children with cerebral palsy (CP) and, if PTS leads to stiff knee gait. MethodsIn a randomized controlled study 22 children with flexed knee gait (age: 10.4 ± 2.6 years, GMFCS Level I–III) were randomized and allocated to two groups (1: SEMLS + PTS; 2: SEMLS no PTS): SEMLS was performed for correction of flexed knee gait either with or without additional PTS. Before and after surgery (follow up: 12.7 ± 1.6 months) kinematics (3-D motion analysis) and clinical parameters were compared. ResultsTwo children were lost to follow up. Maximum knee extension improved significantly in both groups after SEMLS while the patients with additional PTS showed much more correction (SEMLS + PTS: 37.6° to 11.4°, p = 0.007; SEMLS no PTS: 35.1° to 21.8°, p = 0.016). After surgery peak knee flexion decreased significantly (14.6°, p = 0.004) in the “SEMLS + PTS” group while there was no relevant change in the other group. There was a trend of increase in anterior pelvic tilt after surgery in both groups, but no statistical significant difference. After surgery knee flexion contracture (15.9°, p < 0.001) and popliteal angle (27.2, p = 0.009) measured on clinical examination only decreased significantly in the “SEMLS + PTS” group. ConclusionPTS is effective for correction of flexed knee gait and knee flexion contracture leading to superior stance phase knee extension. However, additional PTS may lead to stiff knee gait and a higher increase of anterior pelvic tilt.

The impact of core muscles training on the range of anterior pelvic tilt in subjects with increased stiffness of the hamstrings

The aim of this study is to verify the hypotheses that muscular coordination training of the core region in subjects showing increased hamstring stiffness results in an increase in anterior pelvic tilt and that there is a correlation between hamstring stiffness and anterior pelvic tilt. The two-group, non-blinded experimental controlled trial with three repeated measurements of the dependent variables. The experimental group received muscular coordination training during a period of two weeks, control group – no training. Thirty generally healthy subjects (9 women) were randomly assigned to the two equal groups. Passive knee extension test (hamstring stiffness); the range of anterior pelvic tilt (as measured in neutral standing position and during forward bending of the trunk). A significant decrease in the level of hamstring stiffness was recorded in the experimental group accompanied by an increase in anterior pelvic tilt. No significant changes were observed in the control group. There was a significant, negative, and moderate correlation between hamstring stiffness and anterior pelvic tilt with forward bending of the trunk).

Analysis of gait patterns pre- and post- Single Event Multilevel Surgery in children with Cerebral Palsy by means of Offset-Wise Movement Analysis Profile and Linear Fit Method

Gait analysis is used for the assessment of walking ability of children with cerebral palsy (CP), to inform clinical decision making and to quantify changes after treatment. To simplify gait analysis interpretation and to quantify deviations from normality, some quantitative synthetic descriptors were developed over the years, such as the Movement Analysis Profile (MAP) and the Linear Fit Method (LFM), but their interpretation is not always straightforward.The aims of this work were to: (i) study gait changes, by means of synthetic descriptors, in children with CP that underwent Single Event Multilevel Surgery; (ii) compare the MAP and the LFM on these patients; (iii) design a new index that may overcome the limitations of the previous methods, i.e. the lack of information about the direction of deviation or its source.Gait analysis exams of 10 children with CP, pre- and post-surgery, were collected and MAP and LFM were computed. A new index was designed asa modified version of the MAP by separating out changes in offset (named OC-MAP).MAP documented an improvement in the gait pattern after surgery. The highest effect was observed for the knee flexion/extension angle. However, a worsening was observed as an increase in anterior pelvic tilt. An important source of gait deviation was recognized in the offset between observed tracks and reference. OC-MAP allowed the assessment of the offset component versus the shape component of deviation.LFM provided results similar to OC-MAP offset analysis but could not be considered reliable due to intrinsic limitations. As offset in gait features played an important role in gait deviation, OC-MAP synthetic analysis was proposed as a novel approach to a meaningful parameterisation of global deviations in gait patterns of subjects with CP and gait changes after treatment.

MEASUREMENT OF ANTERIOR PELVIC TILT IN LOW BACK PAIN- AN OBSERVATIONAL STUDY

OBJECTIVE: The objective of the study was to measure the anterior pelvic tilt for both males and females of low back pain patients. STUDY DESIGN: Observational type. PROCEDURE: 120 subjects were approached. In that 70 male and 50 females . Using i@handy application in mobile anterior pelvic tilt was calculated among low back pain patients.RESULTS: Anterior pelvic tilt was increased in low back pain patients . In that correlation between males and Visual analogue scale was not significant. But there was a significant correlation found in female anterior pelvic tilt and Visual analogue scale.CONCLUSION: This study concluded that there was increase in anterior pelvic tilt among low back pain patients. Anterior pelvic tilt and Visual analogue scale was highly correlated in females not in males.KEYWORDS: i@handy, Anterior pelvic tilt, low back pain.

Predictors for anterior pelvic tilt following surgical correction of flexed knee gait including patellar tendon shortening in children with cerebral palsy

IntroductionPatellar tendon shortening procedure within single event multilevel surgeries was shown to improve crouch gait in Cerebral Palsy (CP) patients. However, one of the drawbacks associated to the correction of flexed knee gait may be increased pelvic anterior tilt with compensatory lumbar lordosis. Research questionWhich CP patients are at risk for excessive anterior pelvic tilt following correction of flexed knee gait including patellar tendon shortening? Methods32 patients with CP between 8 and 18 years GMFCS I&II were included. They received patellar tendon shortenings within multilevel surgery. Patients with concomitant knee flexor lengthening were excluded. Gait analysis and clinical testing was performed pre- and 24.1 (SD=1.9) months postoperatively. Patients were subdivided into more/less than 5° increase in anterior pelvic tilt. Preoperative measures indicating m. rectus and m. psoas shortness, knee flexor over-length, hip extensor and abdominal muscle weakness and equinus gait were compared between groups. Stepwise multilinear regression of the response value increase in pelvic tilt during stance phase was performed from parameters that were significantly different between groups. Results34% of patients showed more than 5° increased pelvic anterior tilt postoperatively. Best predictors for anterior pelvic tilt from preoperative measures were increased m. rectus tone and reduced hip extension during walking that explained together 39% of the variance in increase of anterior pelvic tilt. DiscussionEvery third patient showed considerable increased pelvic tilt following surgery of flexed knee gait. In particular patients with preoperative higher muscle tone in m. rectus and lower hip extension during walking were at risk and both features need to be addressed in the therapy.

Distal femoral extension and shortening osteotomy as a part of multilevel surgery in children with cerebral palsy.

There are several reports describing an increase in anterior pelvic tilt after hamstring lengthening in children with cerebral palsy (CP). Distal femoral extension and shortening osteotomy (DFESO) is an alternative treatment for correction of flexed knee gait, but investigations analyzing outcome and influence on adjacent joint are few in the literature. The purpose of this study was to analyze the influence of DFESO on knee and pelvis in children with CP. Furthermore, it was of interest if an additional patellar tendon advancement (PA) influences outcome. In this retrospective study, 31 limbs of 22 children (GMFCS I-III; mean age: 12.1±3.1 years), who received DFESO were included and kinematic parameters (knee, pelvis) measured by 3-D-gait analysis were compared before and at least 1 year after surgery (mean follow-up period: 15.6 months). After surgery, during stance phase minimum knee flexion improved significantly by 20.5° (P<0.001) and mean anterior pelvic tilt increased by 4.0 degrees (P=0.045). In 16 limbs, the postoperative increase in maximum anterior pelvic tilt was more than 5°. Limbs who received an additional PA showed the biggest increase in anterior pelvic tilt. DFESO is an effective method for correction of flexed knee gait in children with CP. Furthermore, the results of this study indicate that DFESO may lead to an increase in anterior pelvic tilt, which may lead to a recurrence of flexed knee gait. In this context, PA seemed to aggravate the effect on the pelvis.

Long term follow up of children post selective dorsal rhizotomy (SDR) – the effect of the adolescent growth spurt on gait

Main topics:Analysis of clinicalmovementdata,Outcomesafter clinical intervention, Rehabilitation Introduction andaim: TheRJAHOrthopaedicHospital has been performing Selective Dorsal Rhizotomy (SDR) procedures for children with cerebral palsy for almost 20 years. Children undergoing SDR have been followed up at regular intervals, including before and after the adolescent growth spurt. Our previously published 18 month follow up [1], showed positive outcomes as a result of careful patient selection. Many patients are now adults and we are reporting thedurability of theoutcomes through theperiodof rapid growth experienced during adolescence. Patients/materials and methods: A cohort of 17 ambulant adults was identified, who had an SDR during childhood (average age 8.4). All patients had been assessed at three time points, preoperatively (PRE) and at two time points postoperatively (POST1 and POST2). POST1 was performed at age 10 for girls and 12 for boys (pre-pubertal) and the POST2 at 16 for girls and 18 for boys (postpubertal). At each time point instrumented 3D gait analysis was performed, along with a full clinical examination. Within subject analysis of variancewas determined using Friedman andWilcoxon signed ranks tests at a significance level of p=0.05 (2-tailed). Results: Table 1. Discussion and conclusions:We are reporting the durability of SDR through the adolescent growth spurt and into adulthood, with an average follow up time at POST2 of 9.7 years post op. The second column in Table 1 compares pre-operative gait data with the outcome post-adolescence. Statistically significant positive changes are observed inmany parameters, including the global measures of gait function (GPS and walking speed). The greatest changes are observed in the parameters most directly linked to spasticity, for example an increasedMaximumRate of Knee Flexion in Swing as a result of reduction in rectus femoris spasticity. The only negative change observed is an increase in anterior pelvic tilt. Positive changes were also seen in clinical examination measures (not reported here). The third column in the table shows the changes during the adolescent growth spurt. Little change is observed during this period, though patients did continue to improve their swing phase knee

Run kinematics with and without a jogging stroller

BackgroundJogging strollers have become increasingly popular as they allow a parent the freedom to run without having to leave their children. Few studies have examined the effects of running with a stroller and no study to date has examined the effects on joint kinematics.The aim of this study was to compare lower limb and trunk kinematics while running with and without a jogging stroller. MethodsParticipants (N=15) ran on a 16-metre indoor runway, with and without a stroller, at their self-selected comfortable training speed. Three-dimensional trunk and lower limb kinematics were assessed using the CODA cx1 active marker system. FindingsThe jogging stroller led to reduced movement of the trunk in both the transverse [mean difference −11.4°, 95% confidence interval (CI) (−14.8°, −8.2°), p<0.001] and coronal [−2.9°, 95% CI (−0.8°, −4.9°), p=0.009] planes most likely due to fixing of the upper limbs. There was also a 6.7° [95% CI (−9°, −4.6°), p<0.001] increase in forward trunk lean, 2.8° [95% CI (−4.2°, −1.7°), p<0.001] increase in anterior pelvic tilt and a 3° [95% CI (−4.4°, −1.5°), p=0.001] decrease in hip extension. There were no significant changes in knee or ankle kinematics and no changes in stride length, cadence or stance time.Interpretation: Our data suggest that jogging strollers lead to minor changes in trunk, pelvis and hip kinematics with no significant changes at the knee and ankle. Due to the changes in kinematics we suggest that flexibility work for the spine, pelvis and hips may be recommended.

Changes in Sagittal Plane Kinematics and Kinetics after Distal Release of Medial Hamstrings in Cerebral Palsy

The purpose of this study is to analyze the effect of distal release of the medial hamstrings on the gait of patients who had spastic cerebral palsy. Twenty-two patients had preoperative and postoperative gait analysis. Standard parameters, such as cadence, velocity, and stride length, were evaluated, as were sagittal plane motion graphs of the pelvis, hip, knee, and ankle, in addition to sagittal plane kinetic analysis. Extension of the knee in stance phase significantly improved postoperatively (p &lt; 0.002), and the improvement was accompanied by a proportional decrease in knee flexion during swing with minimal net gain in the arc of knee motion. Knee range of motion could be improved more by concomitant rectus transfer in selected patients. The statistically significant increase in anterior pelvic tilt (p &lt; 0.002) has been a main concern. There was no significant change in the hip extensor moments or power generation during stance. Increased knee extension during stance after distal release of medial hamstrings is the kinematic gain that improved the gait pattern in cerebral palsy patients. The authors recommend a concomitant rectus transfer to help improve the knee range of motion in patients with rectus over-firing during swing, hence avoiding a stiff knee gait.

Response to letter re: Comparison of hamstring lengthening with hamstring lengthening plus transfer for treatment of flexed knee gait in ambulatory patients with cerebral palsy

We thank the correspondent for his interest and thoughtful questions regarding our paper. We think the two biggest problems following hamstring surgery for flexed knee gait are: (1) achieving adequate correction and (2) maintaining correction over the subsequent years. In order to maximize correction, we maintain patients in solid ankle–foot orthoses (AFOs) for daytime use and ground reaction AFOs for those with more severe involvement, the latter usually temporarily, since the patients frequently find them too constraining; as well as nighttime knee immobilizers for 6 months postoperatively. We have not found any evidence of “overdose” in the patients in this series. All patients in the hamstring transfer plus lengthening (HST) group had lengthening of the semimembranosus and biceps, along with transfer of the gracilis and semitendinosus, while in a few patients in the hamstring lengthening alone (HSL) group, the biceps was left intact. Knee recurvatum did not occur in any patient in this series, probably because we were careful to deal with tight gastrocnemius, when it was present, to avoid pathologic plantar flexion–knee hyperextension couple. Regarding hip extension range and power, there was a small reduction in the HSL group, whereas there was a gain in both parameters in the HST group. Furthermore, hip extension power was preserved or improved in 12/13 patients in the HST group, as compared with only 2/14 in the HSL group. We did not assess step length, but we did look at stride length in those patients walking without assistive devices, and found that there was a statistical increase in stride length in the HST group, and a smaller increase, which was not significant, in the HSL group. However, preoperatively, the HST group had a shorter stride length than the HSL group. We attach the transfer with minimal tension in order not to limit swing phase flexion of the hip, which may explain the difference between our study patients and Gage’s experience. There are many factors which influence pelvic tilt, including balance between hip flexors and extensors, position of the femur relative to the vertical axis, tightness of low back extensors, and balance issues. If a patient with hamstring tightness is walking in 20° of knee flexion, then the femur is canted 20° from the vertical. If the knee flexion is corrected, then the femur will become vertical and the pelvic tilt will be increased by 20°. If the anterior pelvic tilt is increased less than this, then the anterior tilt of the pelvis relative to the femur will actually be improved by reducing the hip flexion. To further reduce the anterior pelvic tilt, the iliopsoas tendon can also be released or lengthened, which may be the primary factor leading to anterior pelvic tilt. There was a period when Dr. Gage felt that, in some patients, knee flexion in gait is secondary to excessive hip flexor activity and/or hip flexion contracture, and knee flexion could be treated by correction of the hip flexion alone. In the HST group, the knee flexion in midstance was improved by 13.7°, and the pelvic tilt increased only by 6.5°. This means that there was about a 7° improvement in hip extension relative to the pelvis, while in the HSL group, the improvement in knee flexion was 8.5° and the pelvic tilt increased by 2.5°, yielding a 6° improvement in hip extension. In conclusion, our major concern was optimizing correction while maximizing motion and power, and minimizing recurrence, rather than “overdose,” which we did not find. We feel that if one treats only 3 of the 4 hamstrings, leaving the biceps intact, then it will remain a deforming force, and lead to lesser correction and more rapid recurrence of deformity, basically an “inadequate dose” of surgery. Every intervention has side effects, and if maximizing the weakening of the hamstrings, by the inclusion of all hamstrings, causes a mild increase in anterior pelvic tilt, but reduces the degree of knee flexion in stance with its negative long-term effects, and propensity to worsen with time, this may be a worthwhile tradeoff. Furthermore, in the transfer patients, there was a gain in both hip extension range and power—certainly no overdose there. Perhaps correction could be maximized and maintained better with patellar tendon shortening, but we have no data on this. If the dose was correct using limited hamstring release, then this patient group would have no need for further bony realignment surgery by anterior hemiepiphysiodesis or osteotomy. We also postulated that moving the tendon attachment sites in the transfer group to above the knee, in order to prevent regrowth to their original attachment site, would decrease the recurrence of knee flexion, which is so common, particularly in younger patients—so stay tuned; hopefully, we will have this data by the end of this year.