Assessment of range and quality of neck movement using a smartphone-based application

This study had the objective of measuring the validity of using a smartphone-based application to measure range of motion (ROM) and quality of movement (QOM) of neck motion by comparing it with 3D-motion capture analysis.

METHODS

Thirty healthy volunteers participated in this cross-sectional study. A helmet fitted with markers for motion capture analysis and a smartphone were fastened to the head of the participants. The smartphone recorded data using a beta version of Balancy (MEDEI, Denmark). Assessments of full active movement in transverse and sagittal planes were performed. Recordings were made simultaneously with the camera system and the smartphone. ROM and jerkiness were compared with a repeated measures ANOVA and a Pearson product moment was calculated to compare the outcomes from the different applications. Bland-Altman plots were generated to determine the levels of agreement.

RESULTS

No difference was found between modalities when comparing measurements of jerkiness or ROM. An excellent Pearson product moment was found for the outcomes of the two modalities for ROM (Pearson's r: 0.83 - 0.96) and jerkiness (Pearson's r: 0.86 - 0.95). The Bland-Altman plot revealed a systemic offset where the phone consistently measured higher values for ROM and lower values for jerkiness.

CONCLUSIONS

This study demonstrated that a smartphone-based application can be used to accurately measure ROM and jerkiness during neck movements. These results indicate the utility of using a smartphone-based application to assess neck movement in humans. The findings have implications for assessment of neck movement in research and clinical practice.

The effect of a compression bandage on the distribution of radiodense contrast medium after palmar digital nerve blocks

BACKGROUND

Studies have shown proximal diffusion of injected drugs in perineural blocks; such diffusion may affect specificity of the nerve block.

OBJECTIVES

To investigate the effect of a compression bandage applied to the pastern region on proximal diffusion of contrast medium injected over the palmar digital nerves.

STUDY DESIGN

Experimental study, randomised cross-over design.

METHODS

Radiodense contrast medium was injected over the lateral and medial palmar digital nerves of the left front limb of nine mature horses. Each horse was injected on two separate occasions, once with a 5 cm wide compression bandage applied proximal to the injection site and once without. The order of the two treatments was randomised with a wash-out period between treatments of at least 7 days. Radiographs were obtained at 5, 10, 20 and 30 min and distribution of the contrast column assessed.

RESULTS

Proximal distribution of the contrast medium was significantly reduced (P<0.01) with compression bandage. Furthermore, the compression bandage inhibited lymphatic drainage of the injected contrast medium.

MAIN LIMITATIONS

Clinical effect of the differences in diffusion length was not assessed.

CONCLUSIONS

The compression bandage reduced proximal diffusion and lymphatic drainage of contrast material causing it to stay localised around the injection site. Use of compression bandages could thus result in increased specificity of the nerve block and potentially prolong its effect.

Vertical movement symmetry of the withers in horses with induced forelimb and hindlimb lameness at trot

Background

The main criteria for lameness assessment in horses are head movement for forelimb lameness and pelvic movement for hindlimb lameness. However, compensatory head nod in horses with primary hindlimb lameness is a well‐known phenomenon. This compensatory head nod movement can be easily misinterpreted as a sign of primary ipsilateral forelimb lameness. Therefore, discriminating compensatory asymmetries from primary directly pain‐related movement asymmetries is a prerequisite for successful lameness assessment.

Objectives

To investigate the association between head, withers and pelvis movement asymmetry in horses with induced forelimb and hindlimb lameness.

Study design

Experimental study.

Methods

In 10 clinically sound Warmblood riding horses, forelimb and hindlimb lameness were induced using a sole pressure model. The horses were then trotted on a treadmill. Three‐dimensional optical motion capture was used to collect kinematic data from reflective markers attached to the poll, withers and tubera sacrale. The magnitude and side (left or right) of the following symmetry parameters, vertical difference in minimum position, maximum position and range‐up were calculated for head, withers, and pelvis. Mixed models were used to analyse data from induced forelimb and hindlimb lameness.

Results

For each mm increase in pelvic asymmetry in response to hindlimb lameness induction, withers movement asymmetry increased by 0.35–0.55 mm, but towards the contralateral side. In induced forelimb lameness, for each mm increase in head movement asymmetry, withers movement asymmetry increased by 0.05–0.10 mm, in agreement with the head movement asymmetry direction, both indicating lameness in the induced forelimb.

Main limitations

Results must be confirmed in clinically lame horses trotting overground.

Conclusions

The vertical asymmetry pattern of the withers discriminated a head nod associated with true forelimb lameness from the compensatory head movement asymmetry caused by primary hindlimb lameness. Measuring movement symmetry of the withers may, thus, aid in determining primary lameness location.

Accuracy and precision of gait events derived from motion capture in horses during walk and trot

This study aimed to create an evidence base for detection of stance-phase timings from motion capture in horses. The objective was to compare the accuracy (bias) and precision (SD) for five published algorithms for the detection of hoof-on and hoof-off using force plates as the reference standard. Six horses were walked and trotted over eight force plates surrounded by a synchronised 12-camera infrared motion capture system. The five algorithms (A-E) were based on: (A) horizontal velocity of the hoof; (B) Fetlock angle and horizontal hoof velocity; (C) horizontal displacement of the hoof relative to the centre of mass; (D) horizontal velocity of the hoof relative to the Centre of Mass and; (E) vertical acceleration of the hoof. A total of 240 stance phases in walk and 240 stance phases in trot were included in the assessment. Method D provided the most accurate and precise results in walk for stance phase duration with a bias of 4.1% for front limbs and 4.8% for hind limbs. For trot we derived a combination of method A for hoof-on and method E for hoof-off resulting in a bias of -6.2% of stance in the front limbs and method B for the hind limbs with a bias of 3.8% of stance phase duration. We conclude that motion capture yields accurate and precise detection of gait events for horses walking and trotting over ground and the results emphasise a need for different algorithms for front limbs versus hind limbs in trot.

Agreement between accelerometric symmetry scores and clinical lameness scores during experimentally induced transient distension of the metacarpophalangeal joint in horses

REASONS FOR PERFORMING STUDY

Equine lameness examination is based on subjective visual scoring of lameness. Instrumented objective methods for lameness examinations may be complicated to perform and the equipment is often stationary. Accelerometry has a potential clinical use; however, the reduction and interpretation of equine accelerometric data are not yet routine and the value of accelerometry in equine lameness examination is unclear.

OBJECTIVES

To use accelerometric data to calculate 2 different accelerometric symmetry scores and to evaluate the agreement of these with traditional lameness scores done by experienced equine practitioners.

METHODS

Six sound horses were equipped with a 3 axis 10G piezoresistant accelerometer at the lowest point of the back. Horses were trotted and video recorded at 0, 3, 15, 30, 45 and 60 min after injection of saline into one metacarpophalangeal joint. Video recordings were scored in a blind manner according to the AAEP scale by 2 experienced practitioners. Interobserver agreements and 2 symmetry scores S and A, developed on the basis of Fourier transformation of the obtained accelerometric data, were calculated and regression analysis between AAEP scores and symmetry scores was performed.

RESULTS

Interobserver agreements were 70%. There was a statistically significant relationship between AAEP lameness scores and both symmetry scores.

CONCLUSIONS

Both symmetry scores showed a significant relationship with the AAEP scores and can be a valuable tool in the detection and quantification of lameness. While the S score was able to detect changes in degree of lameness, the A score was capable of detecting the lame diagonal. However, more research is needed for the development of a combined accelerometric score to take advantage of the strengths of each of the symmetry scores.

Pretreatment of whole-crop harvested, ensiled maize for ethanol production

To have all-year-round available feedstock, whole-crop maize is harvested premature, when it still contains enough moisture for the anaerobic ensiling process. Silage preparation is a well-known procedure for preserving plant material. At first, this method was applied to obtain high-quality animal feed. However, it was found that such ensiled crops are very suitable for bioenergy production. Maize silage, which consists of hardly degradable lignocellulosic material, hemicellulosic material, and starch, was evaluated for its potential as a feedstock in the production of bioethanol. It was pretreated at low severity (185 degrees C, 15 min) giving very high glucan ( approximately 100%) and hemicellulose recoveries (<80%)-as well as very high ethanol yield in simultaneous saccharification and fermentation experiments (98% of the theoretical production based on available glucan in the medium). The theoretical ethanol production of maize silage pretreated at 185 degrees C for 15 min without oxygen or catalyst was 392 kg ethanol per ton of dry maize silage.

Concentrations of serum amyloid A in serum and synovial fluid from healthy horses and horses with joint disease

OBJECTIVE

To determine serum amyloid A (SAA) concentrations in serum and synovial fluid from healthy horses and horses with joint disease and assess the effect of repeated arthrocentesis on SAA concentrations in synovial fluid. Animals-10 healthy horses and 21 horses with various types of joint disease.

PROCEDURES

Serum and synovial fluid samples were obtained from each horse. In 5 of the 10 healthy horses, arthrocentesis was repeated 9 times. Concentrations of SAA were determined via immunoturbidometry.

RESULTS

Serum and synovial fluid SAA concentrations were less than the assay detection limit in healthy horses and did not change in response to repeated arthrocentesis. Synovial fluid SAA concentrations were significantly higher in horses with suspected bacterial joint contamination or infectious arthritis, or tenovaginitis than in healthy controls, and serum concentrations were significantly higher in horses with infectious conditions than in the other groups. Neither serum nor synovial fluid SAA concentrations in horses with low-inflammation joint conditions differed significantly from those in healthy controls. Concentrations of SAA and total protein in synovial fluid were significantly correlated.

CONCLUSIONS AND CLINICAL RELEVANCE

Synovial fluid SAA concentration was a good marker of infectious arthritis and tenovaginitis and appeared to reflect changes in inflammatory activity. The advantages of use of SAA as a marker include the ease and speed of measurement and the fact that concentrations in synovial fluid were not influenced by repeated arthrocentesis in healthy horses. Further study of the SAA response in osteoarthritic joints to assess its usefulness in diagnosis and monitoring of osteoarthritis is warranted.