No link between fracture risk and use of vitamin A-related substances

Vestergaard and colleagues analyze data from a nationwide Danish registry for 124,655 patients who sustained fractures in the year 2000 and 373,962 age- and sex-matched individuals.

Their goal is to arrive at the incidence of fractures in those exposed to systemic vitamin A analogues vs. who those not exposed to these substances.

The researchers control their investigation for possibly confounding factors, such as social variables, contact with hospitals and care providers, alcoholism and any factors known to possibly affect fracture risk, such as use of corticosteroids and anti-epileptic medications.

When Vestergaard and colleagues match one fracture patient each with three controls, they find that neither topical nor systemic vitamin A analogues are associated with the change in fracture risk at any skeletal site.

Furthermore, even large daily doses —14 mg — of vitamin A analogues are not associated with an increased risk of fracture, nor was acne or psoriasis medication.

Reference

Vestergaard P, Rejnmark L and Mosekilde L. High-dose treatment with vitamin A analogues and risk of fractures.Arch Dermatol. 2010;146(5):478-482.

Early (?) Diagnosis of Low-symptomatic Ceramic Acetabular Liner Fracture in Ceramic-on-Ceramic Total Hip Arthroplasty

"Catastrophic" failure of one-piece ceramic liner without major trauma in a very active and heavy patient also having controlateral hip disease and right total knee arthroplasty (asymetric squatting) AND right shoulder arthroplasty for advanced omarthosis with normal rotator cuff (sugar cane handpicking ?)

Alumina ceramics in total hip arthroplasty (THA) have been used in Europe since 1970.

Over the years, ceramic-on-ceramic coupling became a valid option in THA because of excellent biocompatibility and tribological properties.

The major disadvantages are possible squeaking and mainly risk of breakage, usually disclosed by pain and functional impairment.

Squeaking is an audible noise arising from ceramic-on-ceramic bearings, the incidence of which is reported to range from 1% to 7% of THAs.

Component positioning, stripe wear, and edge loading have all been implicated.

Clicking sounds and scratching have also been anecdotally described.

Breakage of a ceramic component due to brittleness of the material still seems a rare complication.

Trauma, high activity level, and obesity may increase the risk of fracture.

Defective ceramic manufacture, inadequate (sandwich with polyethylene) implant design, and errors in surgical technique may contribute to breakage.

Rather than Caucasian, Asian (by extension West Indian) population lifestyle, including squatting, kneeling, and possibly sitting cross-legged, has been correlated to liner rim impingement and fracture.

Additional reports concerning failure of various, mainly sandwich, but not exclusively, ceramic liners have recently been described.

I will describe here a unique case of apparently early diagnosis of a low-symptomatic fracture of an Anca-Fit acetabular liner occurring 3 years after implantation of an uncemented ceramic-on-ceramic modular THA.

Radial Nerve Palsy Associated with Humeral Shaft Fractures

Radial nerve palsy associated with radial shaft fracture is a common occurrence.

Approximately one in ten patients with a humeral shaft fractures will also have associated radial nerve palsy.

In an epidemiologic study of 1.4 million people, the overall incidence of radial nerve palsy in 401 humeral shaft fractures was 8.5%.1

In my own non operative orthopedic study, from 1983 to 1989 of 120 000 people, the overall incidence of radial nerve palsy in 40 humeral shaft fractures is also 8.5% (Basse-Terre, Saint-Claude, Camp Jacob General Hospital, unpublished data).

In a systematic literature review, Shao and investigators2 identified 532 radial nerve palsies in 4,517 radial shaft fractures; an 11.8% incidence of radial nerve palsy.

The management of radial nerve palsy associated with a humeral shaft fracture is a topic of debate.

Although it is known that the majority of these injuries are neuropraxias that will recover spontaneously, the indication and need for operative exploration has been disputed, with authors offering conflicting opinions.

While some surgeons have advocated different treatment algorithms for radial nerve palsies that occur secondary to a closed fracture reduction, others believe that the timing of the nerve palsy is irrelevant to the management decision.

Primary nerve palsies occur at the time of injury and are discovered during the patients initial evaluation.

Approximately 10% to 20% of nerve palsies develop during the course of treatment, commonly noted more often (Basse-Terre)  following an open than a closed reduction, and are termed secondary nerve palsies.3

Complete motor loss is present in 50% to 68% (large majority in Basse Terre) of cases of radial nerve palsy, while the others are only partial motor loss or sensory loss.3

Systematic Literature Review

While some of the studies reported solely on patients with radial nerve palsies, 21 of the studies included the denominator of total radial palsy and shaft fractures.

In these studies, there were 532 radial nerve palsies in 4517 radial shaft fractures; an 11.8% incidence of radial nerve palsy.

Based on the studies that described the fracture location, the highest incidence of radial nerve palsy occurred for fractures in the distal third.

The incidence of palsies was significantly lower for fractures located in the proximal third, then in the middle or distal third.

Table 1. Incidence of radial nerve palsy based on fracture location.

Fracture location	Incidence	# Palsies/# Total fractures
Proximal third	1.8%	1/57
Middle third	15.2%	27/178
Distal third	23.6%	37/157

Transverse and spiral fracture patterns were significantly (P < .001) more likely to be associated with a radial nerve palsy than oblique or comminuted fractures .

Table 2. Incidence of radial nerve palsy based on fracture pattern.

Fracture pattern	Incidence	# Palsies/# Total fractures
Transverse	21.2%	47/222
Spiral	19.8%	19/96
Oblique	8.4%	15/179
Comminuted	6.8%	26/382

They reported no statistical difference in the incidence of radial nerve palsy in open vs closed fractures.²

Table 3. Incidence of radial nerve palsy based in open versus closed fractures.

Fracture Type	Incidence	# Palsies/# Total fractures
Open	18.2%	51/280
Closed	14.8%	137/929

In this literature review, which included a total of 1045 radial nerve palsies, the overall recovery rate was 88.1% (921/1045).

No significant difference in the recovery rate between primary (occurring at the time of injury) and secondary (occurring after the injury, or as a result of a closed reduction) nerve palsies was reported.

The mean time to the onset of recovery, reported in only five studies that included 101 patients, was 7.3 weeks (range: 2 weeks to 6.6 months).

The mean time to full recovery, reported in only five studies that included 110 patients, was 6.1 months (range: 3.4 months to 12 months).

Table 4. Recovery rate of radial nerve palsies.

Type of palsy	Recovery rate	# Recovery/# Total palsies
Overall rate	88.1%	921/1045
Primary	88.6%	632/713
Secondary	93.1%	121/130

Timing of EMG, nerve exploration, and/or tendon transfers

Controversy exists over the recommended timing for surgical exploration of radial nerve palsies.

Debate also exists over whether nerve repair or tendon transfers are the best treatment option for a transacted or permanently injured radial nerve.

Most surgeons suggest obtaining an initial electromyogram at 6 weeks following the injury if there has been no return of radial nerve function.

Thomsen and Dahlin8 recommend an electrodiagnostic examination at 5 to 6 weeks after injury and nerve repair and reconstruction within 2 months, not later than 3 months, after injury.

Ekholm and colleagues1 recommends exploration at 4 to 6 months if there is no resolution following a primary radial nerve palsy.

However for patients with indications for earlier operative fixation (eg, multiple trauma, open fractures, segmental or bilateral fractures, floating elbow, and nonunions), they advocated exploration of the nerve at the time of internal fixation.

Others note that the first sign of nerve recovery may be delayed as long as 6 months following injury.5

Ring and investigators5 suggest basing the timing of operative treatment on the patients willingness to continue wearing a radial nerve brace.

For patients wanting to be brace-free and satisfied with a hand that opens but does not have independent extension, they suggest tendon transfers at 6 months.

For patients who are comfortable wearing a brace, they recommend waiting until 12 months to see if they are one of the patients whose recovery is delayed in nature.

Nerve exploration may be considered in select patients (eg, patients with multiple nerve injuries in whom tendon transfer is not an option) at 6 months.

Verga and colleagues9 reported that in the absence of functional recovery, delayed surgical treatment (neurolysis or nerve grafts) performed 3 to 4 months after primary orthopedic treatment can be useful in achieving good functional recovery and subjectively satisfying results.

My experience is one of conservative treatment with early bracing both of the fracture (Sarmiento functional brace) and of the palsy.

References

1. Ekholm R, Adami J, Tidemark J, et al. Fractures of the shaft of the humerus: An epidemiologic study of 401 fractures. J Bone Joint Surg Br. 2006; 88:1469-1473.

2. Shao YC, Harwood P, Grotz MRW, Limb D, Giannoudis PV. Radial nerve palsy associated with fractures of the shaft of the humerus: A systematic review. J Bone Joint Surg Br. 2005; 87:1647-1652.

3. DeFranco MJ, Lawton JN. Radial nerve injuries associated with humeral fractures. J Hand Surg Am. 2006; 31:655-663.

4. Foster RJ, Swiontkowski MF, Bach AW, Sack JT. Radial nerve palsy caused by open humeral shaft fractures. J Hand Surg Am. 1993; 81:121-124.

5. Ring D, Chin K, Jupiter JB. Radial nerve palsy associated with high-energy humeral shaft fractures. J Hand Surg Am. 2004; 29:144-147.

6. Shah JJ, Bhatti NA. Radial nerve paralysis associated with fractures of the humerus. A review of 62 cases. Clin Orthop Relat Res. 1983; 172:171-176.

7. Holstein A, Lewis GM. Fractures of the humerus with radial nerve paralysis. J Bone Joint Surg Am. 1963; 45:1382-1388.

8. Thomsen NO, Dahlin LB. Injury to the radial nerve caused by fracture of the humeral shaft: Timing and neurobiological aspects related to treatment and diagnosis. Scand J Plast Reconstr Surg Hand Surg. 2007; 41:153-157.

9. Verga M, Peri Di Caprio A, Bocchiotti MA, Battistella F, Bruschi S, Petrolati M. Delayed treatment of persistent radial nerve paralysis associated with fractures of the middle third of humerus: Review and evaluation of the long-term results of 52 cases. J Hand Surg Eur. 2007; 32:529-533.

Bilateral femoral neck fractures due to transient osteoporosis of pregnancy

Figure 1. Antero-posterior radiograph of the pelvis post partum.

Figure 1. Antero-posterior radiograph of the pelvis post partum.

Figure 2. T1 weighted coronal MRI scan of the pelvis post partum.

Figure 2. T1 weighted coronal MRI scan of the pelvis post partum.

Figure 3. Antero-posterior radiograph of the pelvis post fixation with dynamic hip screws.

Figure 3. Antero-posterior radiograph of the pelvis post fixation with dynamic hip screws.

Transient osteoporosis of pregnancy (TOP)

Transient osteoporosis of pregnancy (TOP) is a rare, idiopathic self-limiting condition typically associated with the third trimester of pregnancy.

It almost always affects a single hip although bilateral presentation and involvement of the knee have been reported [1-3].

TOP usually presents with a sudden, quite severe onset of unilateral groin pain with no history of trauma.

The patient may be unable to walk, or may have an antalgic gait.

Pain is elicited by hip rotation, although a full range of motion is common.

Radiographs are avoided in pregnancy where possible, and are a poor investigation for demonstrating early osteopaenia.

Magnetic Resonance Imaging (MRI) reveals low signal intensity of bone marrow on T1 weighted images, and high signal on T2 weighted images suggestive of bone marrow oedema[4].

The natural history is of resolution of symptoms over the course of 3 to 6 months

Hip fracture secondary to TOP

Hip fracture secondary to TOP is very rare with only 12 reported patients in the literature to date; in two cases the hip fractures were bilateral[2,3,5-8].

The majority of these fractures were caused by a traumatic event.

Atraumatic hip fractures secondary to TOP are even more unusual and are easily overlooked and hence may present to the orthopaedic surgeon at a late stage, making management more challenging.

Musculoskeletal complaints are very common in pregnancy.

The position and weight of the gravid uterus alters the centre of gravity and loading patterns of the axial and appendicular skeleton, whilst hormonal changes lead to joint laxity, and fluid retention may cause neural compression[9].

The majority of musculoskeletal complaints are not serious, and are managed conservatively without a specific diagnosis.

Pregnant women frequently complain of hip or pelvic pain.

The differential diagnosis includes some serious problems that need to be excluded, namely

1. transient osteoporosis,
2. osteonecrosis and
3. pubic symphysiolysis.

Conventionally ionising radiation is avoided during pregnancy although Brodell et al. suggested that in the third trimester of pregnancy the benefits of adequate investigation of hip pain may outweigh the minimal risks[5].

MRI during pregnancy

There is no conclusive evidence that MRI has deleterious effects, however the safety of MRI has yet to be definitively proven[10].

It is in common use in the third trimester of pregnancy where clinically indicated[11] and is generally considered to be safe[12].

MRI has a high sensitivity for diagnosis of occult hip fracture[13] and can reliably distinguish between osteonecrosis and transient osteoporosis[4], making it the investigation of choice for hip pain in the third trimester of pregnancy.

Displaced intracapsular fractures have a high incidence of non-union and avascular necrosis[14].

It has however been shown that the risk of non-union is independent of bone quality[15] therefore in young patients with high value hips internal fixation should be the goal.

References

1.	Lloyd JM, Lewis M, Jones A: Transient osteoporosis of the knee in pregnancy. J Knee Surg 2006, 19:121–123. [PubMed]
2.	Aynaci O, Kerimoglu S, Ozturk C, Saracoglu M: Bilateral non-traumatic acetabular and femoral neck fractures due to pregnancy-associated osteoporosis. Arch Orthop Trauma Surg 2008, 128:313–316. [PubMed] [CrossRef]
3.	Munker R, Niedhart C, Niethard FU, Schmidt-Rohlfing B: [Bilateral fracture of the femoral neck following transient osteoporosis in pregnancy]. Z Orthop Ihre Grenzgeb 2007, 145:88–90. [PubMed] [CrossRef]
4.	Takatori Y, Kokubo T, Ninomiya S, Nakamura T, Okutsu I, Kamogawa M: Transient osteoporosis of the hip. Magnetic resonance imaging. Clin Orthop Relat Res 1991, :190–194. [PubMed]
5.	Brodell JD, Burns JE, Heiple KG: Transient osteoporosis of the hip of pregnancy. Two cases complicated by pathological fracture. J Bone Joint Surg Am 1989, 71:1252–1257. [PubMed]
6.	Cohen I, Melamed E, Lipkin A, Robinson D: Transient osteoporosis of pregnancy complicated by a pathologic subcapital hip fracture. J Trauma 2007, 62:1281–1283. [PubMed]
7.	Fokter SK, Vengust V: Displaced subcapital fracture of the hip in transient osteoporosis of pregnancy. A case report. Int Orthop 1997, 21:201–203. [PubMed] [CrossRef]
8.	Wood ML, Larson CM, Dahners LE: Late presentation of a displaced subcapital fracture of the hip in transient osteoporosis of pregnancy. J Orthop Trauma 2003, 17:582–584. [PubMed] [CrossRef]
9.	Smith MW, Marcus PS, Wurtz LD: Orthopedic issues in pregnancy. Obstet Gynecol Surv 2008, 63:103–111. [PubMed] [CrossRef]
10.	Nagayama M, Watanabe Y, Okumura A, Amoh Y, Nakashita S, Dodo Y: Fast MR imaging in obstetrics. Radiographics 2002, 22:563–580. [PubMed]
11.	De Wilde JP, Rivers AW, Price DL: A review of the current use of magnetic resonance imaging in pregnancy and safety implications for the fetus. Prog Biophys Mol Biol 2005, 87:335–353. [PubMed] [CrossRef]
12.	Garcia-Bournissen F, Shrim A, Koren G: Safety of gadolinium during pregnancy. Can Fam Physician 2006, 52:309–310. [PubMed]
13.	Lubovsky O, Liebergall M, Mattan Y, Weil Y, Mosheiff R: Early diagnosis of occult hip fractures MRI versus CT scan. Injury 2005, 36:788–792. [PubMed] [CrossRef]
14.	Lu-Yao GL, Keller RB, Littenberg B, Wennberg JE: Outcomes after displaced fractures of the femoral neck. A meta-analysis of one hundred and six published reports. J Bone Joint Surg Am 1994, 76:15–25. [PubMed]
15.	Heetveld MJ, Raaymakers EL, van Eck-Smit BL, van Walsum AD, Luitse JS: Internal fixation for displaced fractures of the femoral neck. Does bone density affect clinical outcome? J Bone Joint Surg Br 2005, 87:367–373. [PubMed] [CrossRef]