• Scarf osteotomy in the management of symptomatic adolescent hallux valgus.

      Farrar, NG; Duncan, Nicholas; Ahmed, N; Rajan, Rohan (2012-06)
      PURPOSE: This study was designed to assess the utility of the scarf osteotomy in the management of symptomatic adolescent hallux valgus. MATERIALS AND METHODS: This is a case series of 29 patients (39 feet) with a mean follow up of 38.6 months (range 6-60 months). The mean age at the time of surgery was 14.1 years (range 10-17 years). American Orthopaedic Foot and Ankle Society (AOFAS) scores were collected at final follow up, along with a rating of the overall satisfaction. Any complications were recorded. Pre- and post-surgical radiographic angles were measured and analysed using the Student's t-test. The angles measured were the hallux valgus angle (HVA), the inter-metatarsal angle (IMA) and the distal metatarsal articular angle (DMAA). A second surgeon independently reviewed the angles in order to assess the inter-rater reliability using the Pearson product moment correlation. RESULTS: The mean AOFAS score at final follow up was 94.2 (range 54-100). Of all patients, 93 % were either satisfied or very satisfied with their final outcome. One patient has been listed for revision surgery after symptomatic recurrence at 3 years follow up. The pre-operative HVA, IMA and DMAA were 34.8°, 15.9° and 16.0°, respectively. The post-operative values were 16.3°, 8.8° and 9.2°, respectively (p < 0.001 for each). Pearson's r coefficient values demonstrated good inter-rater reliability of measurement. CONCLUSION: We have presented the results of the largest case series of scarf osteotomies for adolescent hallux valgus reported in the literature up to now, as far as we are aware. AOFAS scores at final follow up are comparable to the smaller studies previously reported and provide evidence that good outcomes and high levels of patient satisfaction can be achieved. Early follow up demonstrates a low level of symptomatic recurrence, but longer term data are still required.
    • The formation of the Hand Club: a 60th anniversary.

      Burke, Frank (2012-07)
      Comment in J Hand Surg Eur Vol. 2012 Oct;37(8):803. The formation of the Hand Club: a 60th anniversary.
    • The natural course of traumatic triangular fibrocartilage complex tears in distal radial fractures: a 13-15 year follow-up of arthroscopically diagnosed but untreated injuries

      Lindau, Tommy (2012-08)
      PURPOSE: To evaluate the long-term results of a prospective, longitudinal case series of untreated, traumatic triangular fibrocartilage complex (TFCC) tears found in displaced distal radial fractures. METHODS: Between 1995 and 1997, 51 patients (24 men, 27 women; age, 20-57 y) with a displaced distal radius fracture had wrist arthroscopy to identify associated injuries. Forty-three patients had complete or partial tears of the TFCC, which were not treated. All patients were contacted in 2010, 13-15 years after the injury. One patient had had a TFCC reattachment due to painful distal radioulnar joint instability and was excluded. Thirty-eight patients returned for a radiographic and clinical follow-up that recorded strength, distal radioulnar joint laxity, range of motion, pain scale score, and subjective and objective outcome scores. RESULTS: After 13-15 years, 17/38 patients were lax in the distal radioulnar joint. The mean grip strength was worse in the patients with a lax distal radioulnar joint (83%, SD 15 of the contralateral side vs 103%, SD 33). The median Gartland and Werley score was 5 (good; range, 0-15) in the lax group compared to 1 (excellent; range, 0-9) in the non-lax group, and the median Disabilities of the Arm, Shoulder, and Hand scores were 14 (range, 0-59) and 5 (range, 0-70) respectively. CONCLUSIONS: In this 13-15 year, prospective, longitudinal outcome study of the natural course of TFCC tears associated with distal radius fracture, only 1 patient had been operated on for painful instability since the injury. The subjective and objective results did not provide evidence that a TFCC injury would influence the long-term outcome. However, trends were found and, by speculation, the low number of patients in the series and the risk for a type II error could be the cause of absent statistically significance. Larger, preferably prospective, randomized studies are needed to find out whether a more aggressive treatment is beneficial. TYPE OF STUDY/LEVEL OF EVIDENCE: Diagnostic I.
    • Social implications of balloon kyphoplasty: prospective study from a single UK centre.

      Klezl, Zdenek; Bhangoo, Navjot; Phillips, Jonathan; Swamy, Girish; Calthorpe, D; Bommireddy, Rajendranadh (2012-09)
      PURPOSE: The incidence of osteoporotic fractures is increasing with an ageing population. This has potential consequences for health services, patients and their families. Treatment of osteoporotic vertebral compression fractures (OVCFs) has been limited to non-surgical measures so far. The social and functional consequences of balloon kyphoplasty, a recent development for the treatment of VCF, were assessed in this cohort study. METHODS: Data collected prospectively from 53 patients undergoing balloon kyphoplasty for symptomatic OVCF in our hospital's spinal unit were compared with data from an historical age-matched group of 51 consecutive patients treated conservatively for symptomatic OVCF. Social functionality was recorded prior to the injury, and at 6-month and 1-year follow-up; mortality was recorded at 6 months and 1 year. RESULTS: The mortality rate in the balloon kyphoplasty group was 11 % (6/53) at 1 year post-OVCF, versus 22 % (11/51) in the conservatively treated controls. A drift to a lower level of social functionality (defined by a lower level of independence) was observed at 1 year in 21 % of patients in the balloon kyphoplasty group versus 53 % of patients in the conservatively treated group. A drift to a lower level of independence was noted in 67 % of the conservatively treated patients who started at a lower level of functionality versus 20 % drift in a similar group who were treated with balloon kyphoplasty. CONCLUSIONS: The reduction in mortality and drift in social functionality at 1 year following treatment with balloon kyphoplasty suggests that it is a viable option for the management of OVCFs.
    • A new definition of wrist sprain necessary after findings in a prospective MRI study.

      Lindau, Tommy (2012-10)
      INTRODUCTION: Wrist injuries with negative X-rays are diagnosed as acute wrist sprains. The prognosis is usually good, but some patients suffer from long-lasting pain and reduced wrist function, probably due to missed diagnosis followed by inappropriate treatment. The aim of this study was to investigate acute wrist sprains with MRI to detect the pathoanatomy of the injury. PATIENTS AND METHODS: This prospective magnetic resonance imaging (MRI) study included patients between 18 and 49 years, who attended the Accident and Emergency Department (A&E) Bergen, Norway, after sustaining an acute wrist trauma within the previous week. Initial X-rays of the wrist were normal. MRI was done within a median of 1 day (range 0-31 days) after the trauma, 80% within 4 days. The study period lasted from 5 November 2009 to 4 November 2010. RESULTS: A total of 155 acute MRIs were done, out of which 30 were completely normal. Patients with positive MRI had a median of two (range 0-8) pathological findings. We found 54 fractures and 56 bone bruises, mostly located to the radius followed by the scaphoid, the triquetrum, the capitate and the lunate. There were 73 soft-tissue injuries, which included 15 injuries to the triangular fibrocartilage complex (TFCC) and five scapho-lunate (SL) ligament lesions. CONCLUSIONS: Wrist sprain is an inaccurate diagnosis. In four out of five patients with normal X-rays, MRI identified pathological findings and a large variety of injuries in different structures. We suggest that wrist sprain should be defined as "occult partial or complete soft tissue (ligament, tendon, muscle) or bony injury in relation to a trauma with negative X-ray". The MRI findings led to a more differentiated treatment in more than a third of the patients. We recommend that MRI should be considered as a part of an early investigation, especially when the wrist pain does not settle within the first couple of weeks.
    • Fixed flexion deformity following total knee arthroplasty. A prospective study of the natural history.

      Quah, Conal; Swamy, Girish (2012-10)
      INTRODUCTION: Stiffness following total knee arthroplasty (TKA) is a disabling problem resulting in pain and reduced function. OBJECTIVE: The aim of our study was to evaluate the natural course of fixed flexion deformity (FFD ) following primary total knee arthroplasty. METHODS: Prospective review of 1626 patients undergoing primary TKA from 2001 to 2006 with a minimum of 4 year follow up. Demographic data included post-operative range of motion; type of prosthesis used, treatment modalities for stiffness and the final range of motion were recorded. FFD was defined as class 1(5-15 degrees) and Class 2 (> 15 degrees). Patients with a pre-operative FFD of >15, infection, stiffness treated with manipulation or revision surgery were excluded from the study. RESULTS: Of the 1626 patients evaluated, 170 (10.5%) presented with a FFD. 18 patients were excluded from the study and 16 were lost to follow up. 124 (91.2%) were class 1 and 12 (8.8%) were class 2. FFD improved from a mean of 8.8 degrees to 0.4 degrees (p<0.0001) in 11.4 months. In 94.1% patients the FFD completely resolved (i.e. < 5 degrees) at a mean of 10.8 months (p<0.0001). In the remaining 5.9% of patients, FFD improved from a mean of 16.4 to 6.9 degrees at a mean follow up of 21.5 months (p<0.0001). CONCLUSION: A gradual improvement in the FFD can be expected up to 2 years and a small residual flexion contracture does not cause functional deficit. LEVEL OF EVIDENCE: Prospective cohort study, level 3.
    • Anterior cruciate ligament reconstruction complicated by pyoderma gangrenosum.

      Bagouri, Elmunzar; Smith, Jon; Geutjens, Guido (2012-11)
      We report a case of pyoderma gangrenosum as a complication of an anterior cruciate ligament reconstruction in a patient with inflammatory bowel disease, which was misdiagnosed initially as a post-operative wound infection. An early dermatology opinion and skin biopsy should be considered in cases of suspected infection where thorough surgical debridement and antimicrobial therapy has failed to improve the clinical picture.
    • Endovascular repair of iatrogenic popliteal artery trauma.

      Saunders, JH; Subramonia, S (2012-12)
      PURPOSE: To evaluate the outcome of the management of iatrogenic arterial injuries following knee arthroplasty using a primary endovascular approach. METHODS: A detailed review of the management of all iatrogenic arterial injuries to the lower limb following total knee arthroplasty (TKA) referred to the Vascular Surgical Unit of a tertiary referral hospital between July 2005 and December 2007 identified from a prospectively maintained database. RESULTS: Of the seven cases referred over a 30-month period, six patients underwent endovascular treatment with successful limb salvage. All seven injuries were related to the popliteal artery behind the knee: pseudoaneurysm (4), intimal flap occlusion (2) and stenosis (1). One patient underwent above-knee amputation. The presentation and pattern of arterial injuries, potential risk factors for their occurrence, measures to reduce their risk and factors that aid in their early recognition are discussed. CONCLUSIONS: An endovascular approach may be considered for the management of these injuries, although it is likely to involve long-term surveillance and may not be appropriate for all cases. Surgeons performing TKA should be aware of the potential risk factors for arterial injury and maintain a high index of suspicion for these infrequent injuries during the post-operative period.
    • Magnifying loupes versus microscope for microdiscectomy and microdecompression.

      Yellu, Sunil; Bommireddy, Rajendranadh (2012-12)
      STUDY DESIGN: Consecutive case series of 51 patients in each group--single-surgeon experience. OBJECTIVE: Comparing magnifying loupes and microscopes for microdiscectomy and microdecompression. SUMMARY OF BACKGROUND DATA: Prospective peroperative data and retrospective outcome data. METHODS: All patients had unilateral single-level magnetic resonance imaging-proven radicular pain. All relevant preoperative, peroperative, and postoperative data were collected prospectively, including operating time, complications, and return to the preprolapse functional level. Retrospective patient satisfaction, employment level, workman's compensation claim status, smoking status, pain, and functional outcome scores were collected through a telephonic interview. RESULTS: The microscope group was significantly (P < 0.05) better than the loupes group with respect to patient outcome and earlier return of the preprolapse functional level. Patient satisfaction scores, Visual Analogue Scores for pain, and rate of complications were also better in the microscope group but were not statistically significant at P < 0.05. CONCLUSIONS: Microscopes are better than loupes as they provide a much better visualization, are more comfortable for the surgeon, and are a much better teaching tool.
    • Wound healing with medications for rheumatoid arthritis in hand surgery.

      Barnard, AR; Regan, Marian; Burke, Frank; Chung, Christopher; Wilgis, E (2012-12)
      Introduction. Medications used to treat rheumatoid arthritis, such as corticosteroids, disease-modifying agents (DMARDs), and injectable biological agents (anti-TNFα), may have widespread effects on wound healing. In hand surgery, it is important to balance the risks of poor wound healing from continuing a medication against the risks of a flare of rheumatoid arthritis if a drug is temporarily discontinued. Materials and Methods. A United Kingdom (UK) group of 28 patients had metacarpophalangeal joint replacement surgery in 35 hands (140 wounds). All medication for rheumatoid arthritis was continued perioperatively, except for the injectable biological agents. Results. There were no instances of wound dehiscence or deep infection and only one episode of minor superficial infection. Conclusions. We conclude that provided care is taken to identify and treat any problems promptly, it is appropriate to continue most antirheumatoid medications in the perioperative period during hand surgery to reduce the risk of destabilising the patients' overall rheumatoid disease control.
    • Is ultrasound diagnosis reliable in acute extensor tendon injuries of the knee?

      Swamy, Girish; Nanjayan, Shashi; Yallappa, Sachin; Bishnoi, Amir; Pickering, Simon (2012-12)
      Ruptures of the patellar and quadriceps tendon are rare injuries requiring immediate repair to re-establish knee extensor continuity and allow early motion. Ultrasound is extensively used as a diagnostic tool before surgery on acute traumatic tears of the patellar tendon and quadriceps tendons. The aim of our study was to evaluate the role of sonography in diagnosing quadriceps and patellar tendon rupture and in differentiating partial from complete tears. We conducted a retrospective review of 51 consecutive patients who had a surgical intervention for suspected acute quadriceps and patellar tendon rupture over a 5-year period. Intra-operative findings were compared with pre-operative clinical examination. Radiographs, ultrasound and MRI reports were reviewed. On clinical examination, 22 patients had a suspected patellar tendon rupture and 29 patients had a suspected quadriceps tendon rupture. Diagnosis was confirmed by clinical examination and plain radiographs alone in 13 patients, with additional ultrasound performed in 24 patients and MRI scan performed in 14 patients. There were 8 false positives out of 24 [33.3%] in the ultrasound proven group and 1 false positive out of 13 [7.69%] in the clinical examination and radiographs only group. MRI was 100% accurate. We conclude that ultrasonography is not a reliable method in establishing the diagnosis of acute injuries to the extensor mechanism of the knee, particularly the quadriceps tendon ruptures in the obese and the very muscular patients. If there is clinical ambiguity, MRI scan is a better investigation tool before undertaking surgical treatment.
    • Cervical spondylotic myelopathy: the outcome and potential complications of surgical treatment.

      Sherief, T; White, Jonathan; Bommireddy, Rajendranadh; Klezl, Zdenek (2013)
      PURPOSE OF THE STUDY: Cervical spondylotic myelopathy is the most common cause of spinal cord dysfunction in patients over 60 years old. Symptoms often develop gradually and insidiously and are characterized by neck stiffness, arm pain, numbness and clumsiness of hands, as well as weakness of the hands and legs frequently leading to a change in mobility. Surgery is performed primarily to prevent the progression of symptoms but also with the aim of improving existing symptoms. Aim of our study was to assess the outcomes and potential complications of surgical decompression of cervical spondylotic myelopathy (CSM). MATERIAL AND METHODS: Prospective data was collected from 71 patients who were treated surgically for CSM over a four-year period (June 2006 to June 2010). Only patients with confirmed spondylotic cervical myelopathy were included in the study; those with an inflammatory, infectious or neoplastic etiology were excluded. The Nurick scale was used as a primary outcome measure, and the improvement in upper limb function as a secondary outcome measure. Statistical significance was assessed using the paired t-test. RESULTS: 34/71 (47.9%) patients had an anterior decompression, 36/71 (50.7%) patients underwent posterior surgery and one patient (1.4%) received a combined approach: The Nurick score: The mean score improved by 0.9 from 2.4 preoperatively to 1.5 postoperatively for the whole series. Three patients were able to return to work. The preoperative Nurick score showed a positive correlation with the postoperative Nurick score at one year (Pearson Coefficient = 0.85). Upper limb symptoms: Postoperatively, 24 patients were free of any upper nlimb involvement compared with 6 patients preoperatively. The main improvement was in patients who prior to surgery had subjective symptoms with no objective signs of weakness or muscle wasting. 35/48 (72.9%) of this group showed improvement compared to 7/17 (41.2%) of patients who demonstrated objective weakness and/or wasting preoperatively. COMPLICATIONS: The overall rate of complications was 18.2%. There were two mortalities as a result of pneumonia (2.8%), one patient had to be transferred to the intensive care unit for cardiac failure (1.4%), fixation failure occurred in two patients (2.8%), worsening of myelopathy occurred in two patients (2.8%), C5 temporary radiculopathy presented in two patients (2.8%), superficial wound infection developed in one patient (1.4%) and three patients (4.2%) complained of severe axial pain in the postoperative period. DISCUSSION Our results demonstrate that the greater the preoperative disability the greater the final disability is expected to be. Cord signal change, as an indicator of the pathological severity of the disease, correlates with a worse functional outcome. The degree of improvement postoperatively (i.e. the functional change) does not show a significant correlation with the initial preoperative status. It appears however, that there is a better chance of improvement in patients with no objectively detectable weakness or muscle wasting. The rate of complications encountered in this series is comparable with those in the literature, which renders them valid for quoting when considering surgical treatment for CSM. CONCLUSION: Surgical decompression offers a real chance of improvement in the functional outcome of CSM, especially during the earlier stages of the disease. The surgical decision needs to be considered carefully due to the advanced age of the patient population and the greater burden of co-morbidities, which increase the surgical risks significantly.
    • Chylous ascites: Why exercise is bad for you.

      Tewari, N; Bhalla, Ashish; Iftikhar, Syed (2013)
      INTRODUCTION: The development of chylous ascites is usually associated with trauma, iatrogenic or otherwise. Blunt abdominal trauma producing hyperextension or hyperflexion may cause disruption to lymphatic vessels causing chylous ascites. PRESENTATION OF CASE: This report describes the case of a 38-year-old gentleman who presented to the emergency department with severe abdominal pain after completing a triathlon. As the patient was in severe pain, an abdominal CT was performed which demonstrated a possible mid gut volvulus. Subsequent laparotomy noted a significant volume of intra-abdominal chyle with no other abnormalities. DISCUSSION: This is the first report of chylous ascites occurring without associated abdominal pathology after a period of strenuous exercise. CONCLUSION: Chylous ascites can occur as a result of hyperreflexion and hyperextension injuries sustained during strenuous exercise.
    • Efficacy and safety of collagenase clostridium histolyticum injection for Dupuytren contracture: short-term results from 2 open-label studies.

      Lindau, Tommy (2013-01)
      PURPOSE: The JOINT I (United States) and JOINT II (Australia and Europe) studies evaluated the efficacy and safety of collagenase clostridium histolyticum (CCH) injection for the treatment of Dupuytren contracture. METHODS: Both studies used identical open-label protocols. Patients with fixed-flexion contractures of metacarpophalangeal (MCP) (20° to 100°) or proximal interphalangeal (PIP) joints (20° to 80°) could receive up to three 0.58-mg CCH injections per cord (up to 5 total injections per patient). We performed standardized finger extension procedures to disrupt injected cords the next day, with follow-up 1, 2, 6, and 9 months thereafter. The primary end point (clinical success) was reduction in contracture to within 0° to 5° of full extension 30 days after the last injection. Clinical improvement was defined as 50% or more reduction from baseline contracture. RESULTS: Dupuytren cords affecting 879 joints (531 MCP and 348 PIP) in 587 patients were administered CCH injections at 14 U.S. and 20 Australian/European sites, with similar outcomes in both studies. Clinical success was achieved in 497 (57%) of treated joints using 1.2 ± 0.5 (mean ± SD) CCH injections per cord. More MCP than PIP joints achieved clinical success (70% and 37%, respectively) or clinical improvement (89% and 58%, respectively). Less severely contracted joints responded better than those more severely contracted. Mean change in contracture was 55° for MCP joints and 25° for PIP joints. With average contracture reductions of 73% and improvements in range of motion by 30°, most patients (92%) were "very satisfied" (71%) or "quite satisfied" (21%) with treatment. Physicians rated change from baseline as "very much improved" (47%) or "much improved" (35%). The CCH injections were well tolerated, causing no tendon ruptures or systemic reactions.CONCLUSIONS: Collagenase clostridium histolyticum was an effective, minimally invasive option for the treatment of Dupuytren contracture of a broad range of severities. Most treated joints (625 of 879) required a single injection. Treatment earlier in the course of disease provided improved outcomes. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.
    • Risk factors in lateral epicondylitis (tennis elbow): a case-control study.

      Titchener, Andrew; Fakis, Apostolos; Tambe, Amol; Smith, C; Hubbard, R; Clark, David (2013-02)
    • Legg-Calvé-Perthes: interobserver and intraobserver reliability of the modified Herring lateral pillar classification.

      Rajan, Rohan; Chandrasenan, Jeevan; Price, Kathryn; Konstantoulakis, Chrompolis; Metcalfe, James; Jones, Stanley (2013-03)
      The purpose of our study was to independently assess the reliability of the modified Herring lateral pillar classification. METHODS: Thirty-five standardized true anteroposterior radiographs of children in the fragmentation phase were independently assessed by 6 senior observers on 2 separate occasions (6 wk apart). The κ analysis was used to assess the interobserver and intraobserver agreement. RESULTS: Intraobserver analysis revealed at best only moderate agreement for 2 observers. Three observers showed fair consistency, whereas 1 remaining observer showed poor consistency between repeated observations (P < 0.01). The highest scores for interobserver agreement varying between moderate to good could only be established between 2 observers. For the remaining observers results were just fair (P < 0.01). CONCLUSIONS: This study highlights the lack of agreement between senior clinicians when applying the modified lateral pillar classification. The results from the Herring group were significantly better than ours, but utilized a weighted κ for analysis, which may have given artificially high scores. To our knowledge, this is the first time the modified lateral pillar classification has been independently tested for its reproducibility by a specialist pediatric orthopaedic unit.
    • Anterolateral surgical approach to the malunited distal radius fracture for corrective osteotomy and bone-graft harvest.

      Mathew, Philip; Garcia-Elias, Marc (2013-03)
      The most common complication after distal radius fractures is union with deformity. When symptomatic, distal radial malunions may require operative intervention. Numerous approaches to the distal radius have been described. Most volar approaches involve sectioning the brachioradialis and opening the first extensor compartment to permit adequate exposure. When bone graft is required, this may necessitate a separate incision and further add to the morbidity. We present an alternative anterolateral surgical approach to the distal radius, which allows for excellent exposure, and minimal trauma to the tendons while permitting harvest of local bone graft through the same incision.
    • Tertiary syphilis in the cervical spine: a case report and review of the literature.

      Salem, Khalid; Majeed, H; Bommireddy, Rajendranadh; Klezl, Zdenek (2013-03)
      As the prevalence of syphilis rises, an increase in tertiary syphilis with spinal involvement is predicted. We report what we believe to be the first case of compressive cervical spine syphilitic gummata, with central cord compression signs. We also review the relevant literature to date. The diagnosis of syphilis in the spine relies on the physician to be aware of it as part of the differential diagnosis. Treponemal laboratory tests are an important aid in establishing a diagnosis.
    • Early prognostic factors in distal radius fractures in a younger than osteoporotic age group: a multivariate analysis of trauma radiographs.

      Lindau, Tommy (2013-05)
      BACKGROUND: Treatment of distal radius fractures in patients of a younger than osteoporotic age is complex, because they often are the result of a high-energy trauma and have intra-articular fractures and associated injuries. As yet no fracture classification exists that predicts outcome. Our aim was to find the earliest possible prognostic factor by testing which radiological parameter on the trauma radiograph would have the greatest impact on clinical outcome in a younger than osteoporotic age group. METHODS: We assessed 66 patients (34 F) with unilateral fractures of the distal radius from a non-Osteoporotic age group. The median age was 42 years, (10th -90th percentile 20-54). Pre-reduction antero-posterior and lateral wrist radiographs were obtained and fracture pattern, radiocarpal joint surface tilt, radial length, radial inclination and ulnar variance were measured. Clinical outcome was assessed with the subjective part as well as the complete modified Gartland and Werley score. Multivariate analysis of those parameters was performed to assess which radiological parameter would best predict outcome. RESULTS: It was found that post-traumatic ulna + (>2 mm) was the single factor that significantly correlated with a bad outcome. An intra-articular fracture pattern may also be a strong marker; however this was not statistically significant (RR 95% conf interval 0.94 - 20.59). CONCLUSIONS: The present study showed that post-traumatic ulna + is the most important factor in predicting bad outcome in non-osteoporotic patients, but that especially intra-articular fractures and to a lesser extent dorsal tilt may be of importance too.